Green Building Forum - All Discussions

New old cottage - what wood-burner, what insulation?

Dan McNeil — Sun, 20 Jan 2008 19:47:39 +0000

Hello all,

Hereâ€™s hoping you can give me your thoughts and adviceâ€¦

Weâ€™ve recently moved into a small end-terrace cottage (circa 1750). Solid stone walls, solid floors downstairs, double-glazing, open fireplace and a hideous mix of old storage and convector heaters. Weâ€™ve just insulated the loft, which has made a noticeable difference (at least it feels like it has) to the retained warmth upstairs. Further plans are to internally insulate the (external) walls, and install a central heating system fired by a wood-burner (no gas in the village, but plenty of wood available). My questionsâ€¦

1. Wood-burner â€“ we obviously need one with a backboiler to heat the DHW, and weâ€™d hope to be able to heat some rads as well. Thing is, we really want a contemporary wood-burner. If we were to heat DHW and some rads, then weâ€™re limited to the Firebelly FB2 if we go for contemporary. Love the looks, so we went to see one at the weekend, and were so disappointed. Appalling build quality â€“ hopeless paint finish, nasty exposed welds, tinny side panels, clunky levers, clanging door handle, shoddy panel gaps and door shut-lines. The Firebelly badge was glued onto the door and was wonky. If it were a car, itâ€™d be an original Land Rover Discoveryâ€¦.

We did have one thought, which was to go for a wood-burner with enough of a boiler to heat just the DHW (the Hwam Monet is a serious thought, very pricey, but the build quality is in a different league to the Firebelly, you can see why they cost so much, it was everything the Firebelly wasnâ€™t). Our thought was - could we heat the rest of the cottage with the warm air from the stove, perhaps assisted by installing discreet vents in the ground floor ceilings, to assist with air circulation? Weâ€™ve seen a type of fan that sits on or close to the burner, no batteries, powered by the burnerâ€™s heat. Apparently theyâ€™re very good at shifting heat.

The cottage footprint is approx 4.9 x 5.6 metres. Downstairs is the living room (4.9m x 3.2m) and kitchen (3.9m x 2.4m), with a tiny porch front and rear. Upstairs are three small bedrooms and a small bathroom, all leading off a tiny (1m x 1m) landing. Ceiling height on both levels averages about 2 metres. The short stairwell comes off the living room. The Hwam Monet with boiler is an 8kw stove, with 3.1kw to the water. Does anybody think this could heat the whole cottage? If not, and we want rads plus DHW powered by the wood-burner, we seem to be stuck with a typical boring black box, such as the Stratford (Iâ€™ve heard good things about this stove, and they sound pretty good value or a Woodwarm (the consensus seems to be that theyâ€™re OK but over-priced).

2. Internal wall insulation â€“ weâ€™ve heard different opinions on whether to have an air gap between the chosen type of internal boards (weâ€™re looking at thermal plaster board) some say attach directly to the wall, others say attach a framework of battens first, to allow an air gap. The latter sounds more logical to me.

3. Central heating â€“ does anybody have any opinion on the type of system to install with a wood-burner? Weâ€™d prefer to not rely on electricity, e.g. pumps, so thermosyphoning (hope Iâ€™ve spelt it right) is something Iâ€™ve heard of that sounds suitable? We also want to install solar hot water heating (in a year or so, when weâ€™ve got some more cash!), so any new water tank would need to have the ability to connect to this.

Apologies for all the questions! Hope to hear some useful advice.

Thanks,
Dan.

"u" Values Laboratory and Site, Theory and Reality

sipman — Sat, 19 Jan 2008 09:55:59 +0000

The code for sustainable homes calls levle 6 calls for "u" values of 0.11

When undertaking Sap calculations and Space heating requirments we enter theoretical "U" values that i presume have been achieved in laboratory conditions.

Has any testing ever been undertaken to see in reality what U values have been achieved on site

Do we need U values as low as 0.11 to achive Passive house standards in the uk, or do we just have to ensure better site practice and make better use of levels of insulation used today

Sipman

German or Italian underfloor heating?

Peter A — Wed, 10 Oct 2007 19:37:38 +0100

Hi, I had a strange conversation the other day about wet underfloor heating, apparently there are two types! Italian and German, in the UK we use the Italian system that involves lots of control valves and pushes the price up. Does anybody know a bit more about the German system, it's not used in the UK because you can't get a good mark up on just selling pipes.

Naffness of block paving

tony — Sat, 19 Jan 2008 11:48:12 +0000

Block paving has been popular for the last few decades and we now seeing some of the greener aspects of it

Moss, grass, weeds, vegetation all causing slow decay processes to speed up.

It all looks great the day it goes down but after a while with mo maintenance nature Creeps in round the edges and starts it work.

Regular maintenance seem no to happen very much on private driveways.

Why doesn't this seem to happen in town centre locations? do they treat it with weed killers?

garden-based remote solar water heating array ideas

TheDoctor — Wed, 09 Jan 2008 16:32:39 +0000

thinking ahead a year or two...

Our current refurb / extension will have a solar compatible HWC fitted, as i plan to link it in to a series of panels in the future.

The problem is that the house is orientated North South (long thin Scottish Steading) with a tree in front of the small South hip of the roof. Not ideal!

I do, however, have a reasonably big garden, no neighbours (in any direction, and the ability to put a ground sited solar array in and make a feature of it.

so, questions.

1/anyone done this before?

2/how far from the cylinder can this type of thing be? (current siting thoughts would put it 25m from the house, and 30 or so from the cylinder)

3/if the cylinder is marginally above the array, is this a problem?

4/are big pumps needed?

5/should the array be a long straight line facing South, or should it be a slight curve, picking up a bit of East and bit of West too?

6/am i daft to consider this?

7/It is still worth it in Scotland?

I am going to study the sun/shading patterns in the garden throughout this year to optimize the location.
I am trying to solve it now, so that i can build in tails to the outside now to save disruption in the future.

Drying the washing.

david — Fri, 18 Jan 2008 20:12:29 +0000

My new house has a Whole House Ventilation with Heat Recovery system.
Should I vent the tumble drier to the outside ,or should I let the moisture and heat into the house, recover 80% of the heat via heat recovery and exhaust the moisture?
Should I even have a tumble drier?
I could have a drying rail hanging in the utility room and put a bit of extra heat in there.

Central Heating

becinda — Sat, 19 Jan 2008 10:19:33 +0000

Hi everyone,
We are in the process of buying a run down terrace house. We are very keen to have a wood burning stove in there and the house has already got a gas supply but no heating. We are wondering if it's possible to combine a gas boiler and a back boiler on a multifuel stove to provide central heating for the house?

Window Insulation Film- Help!!!

johnwoods — Tue, 18 Dec 2007 22:40:26 +0000

Please Help!!!!
I have just purchased a house and its freezing!!
The heating seems to warm the place- only to go cold again within minutes of turning it off.
I checked the problem out and its the windows!
I came across this site www.window-insulation.co.uk
I have ordered four packs- has anyone used this item?
How effective is it??
Would appreciate any help at all!!
Cheers
John.

Tyres and Soakaways

Peter A — Sun, 20 Jan 2008 19:31:10 +0000

Thought I'd better get round to getting my extension signed off, only had a soakaway to put in. Got a quote from the groundworker working next door, the Â£3750 price tag made me cough a bit. Thought about it for a while and decided to do it myself. Three weekends later with the hole dug I popped down to Kwikfit picked up 7 of the biggest car tyres they had, drilled some holes in their walls, stacked them neatly in the hole, laid a bit of pipework and capped it all off with a york stone paving slab from the top of the garden, all for the cost of a skip (Â£140) and a bit of drainage (Â£80). Got the extension signed off and not had any issues with all that rain recently.
Then somebody said it wasn't environmentally friendly to use car tyres that way because of the deposits on them from driving on roads, personally I think it's ok, what else would they be used for.
Penny for your thoughts?

Fire retardant free sofas?

aviatrix — Fri, 18 Jan 2008 22:21:10 +0000

Hello, Does anyone know where sofas that have not been treated with fire-retardants can be found?

How far can I change a traditional conservatory?

DavidND — Tue, 09 Oct 2007 21:14:13 +0100

We've just bought a house with a, 'worn out' with a capital K!, conservatory. Its traditional double wall polycarb roof and knackered dg units. I want to raise the dwarf walls to normal height (and fully insulate) have a wall of glass at the end (triple glazed) and put a very well insulated tiled roof on with a single velux (or similar).

Some questions:
a) can I just do it? or
b) would I need planning permission?
c) does teh fact I want to conserve energy have ANY clout whatsoever?

Thanks in advance peeps.

external render

snowy1988 — Sun, 20 Jan 2008 10:53:31 +0000

We are renovating a double brick house c. 1900. The house had severe water ingress when we bought it - we thought mainly rising damp and ingress round windows. We've dug out floors and poured concrete and tanked external walls up to 1m. Have stripped off all plaster and were about to instal Gyproc Thermaline insulated plasterboard internally. However, during the heavy rain of the last week, rain has penetrated the front wall. This is not just through mortar joints but also through decayed bricks. We have thought of rendering the internal face of the external walls but are now wondering if we should bite the bullet and render externally. Should we do this and if so what mix should we use? We are doing our best to be green (solar panels, GSHP, renewable insulation where we can) but are struggling with some aspects.

condensation in rented houses?

worried — Fri, 18 Jan 2008 19:45:49 +0000

hello all
i'm new to this website and may be talking in the wrong place...
i am really looking for advice as i am unsure what the problem is.
my concerns are manyfold:
i am currently renting an end of terrace 1900ish property and as such have adhered to the anti-mould/anti-condensation advice given to me by the letting agents. (shut the bathroom door, air the house, leave the heating on etc etc)
however, despite this, we are on the verge of being penalised for 'condensation' because our house has suffered severe problems of damp.
upon pulling the sofa further away from the wall ( we left it where it was placed wbout 6 inches from the wall) we found white crystally mould and the skirting board coming away from the wall. Behind the bookcase is black spotted mould. In addition to this the plaster is cracking along the wall lines along most exterior walls and the floor boards are warping to an extent where the door is becoming difficult to open and close. also, when we moved in the shower head and sink plug were hanging with black slime which i had to clean with bleach.
having described the problems to the letting agency, they have claimed that the problems are entirely our fault as tenants.
having lived in about 10 let properties and never having encountered these problems before, i'm looking for advice in this area. i have never encountered this kind of mould/damp. could it have been just condensation or is it likely to be rising damp?

i would also like to question whether letting properties with the advice of 'keep[ing] the heating on low all day - even when there is no one at home'' and 'keep[ing] a small window ajar when someone is in the room' is an acceptable ask of tenants who are environmentally conscious ...

Part L1B 25% rule

Justin — Fri, 18 Jan 2008 21:25:32 +0000

Hi,
Section 15 reads:

"..plus
b. The area of any windows or doors which as a result of the extension works, no longer exist or are no longer exposed"

So can "windows which no longer exist" be in a different part of the dwelling to the area of the extension? I'm unsure quite what's meant by "as a result of the extension works". Clearly openings specifically covered over by the extension are additional basic allowance, but do openings which I might shrink or cover over elsewhere in the dwelling during the same work, also add classify as an additional allowance against the 25% rule?

(Yes I'm aware of the "optional approaches", and have been looking carefully at those, but want to ensure I've fully understood this basic one first)

cellotex vs kingspan when insulating skeilings

mzthomps — Thu, 17 Jan 2008 14:22:17 +0000

Following other threads on this forum I am planning to insulate some skeilings in my house using 50mm air gap/50mm polyurethene ridged type insulation between the rafters (e.g. Kingspan K7 or Cellotex GA3000)/ 50 - 75mm polyurethene backed plasterboard (e.g. Kingspan K18).

Looking at the various products wondered if anyone could tell me the difference between Cellotex GA3000 and Kingspan K7 or Kingspan Thermapitch. The Cellotex appears to be about third of the price of the Kingspan.

Thanks.

Drowning walls.

david — Sun, 13 Jan 2008 19:53:53 +0000

It's beeen pouring rain and blowing a gale for days here and the walls of our house are soaked. The construction is designed to cope with this. There's an outer leaf of stone pointed with lime mortar, a space filled with small rubble and air and an inner leaf of stone, in all about 900mm thick, so the water can't get through. The inner surface is insulated.
I read a lot about newer methods of external wall construction, particularly about a system called breathing wall which I understand to be vapour permeable constructions of one or many layers.
How can water vapour inside a building wall pass through the walls to the outside when the humidity is higher outside?
This seems to be the situation for most of the time here.
Does the breathing wall breathe both ways and allow water vapour to pass into the building when the internal humidity is lower?
We try to always have our house drier than outside!
Is the wall cooled when the water within it evaporates?
If so how does this affect U values?

Would you consider renewable energy for ethical reason?

Petethepole — Thu, 17 Jan 2008 22:01:31 +0000

If the use of renewable energy does not make economical sense..... what does??????????????????????
Kent based Renewable Energy Expert.
Best Regards to All
:bigsmile:

We sell SIPS panels in Mexico at wholesale prices!!

bertram — Fri, 18 Jan 2008 01:17:18 +0000

We sell SIPS panels in Mexico at wholesale prices we also build residential and comercial at discount prices, visit our website www.sipsdemexico.com or call us (619) 308-8304 or in Mex. (664)290-3578 and 79 ask for Jose Bertram.

Resilience of systems

Chris Wardle — Thu, 17 Jan 2008 12:57:54 +0000

This is an excuse to recommend an excellent book I've just read called "The Upside of Down" by Thomas Homer-Dixon.

He talks about the danger of our civilisation suffering from "synchronous failure", caused by a convergence of stresses, such as climate change, oil depletion, terrorism and economic instability, and this resulting in collapse of our economic, political and social orders. He recommends we prepare for such a scenario by building resilience into our systems such that we can survive the breakdown of critical systems and be in a better position to regenerate and transform our societies.

I think this is relevant to the way we build and in particular to building services. For example, if you rely on grid electricity for ventilation, heating, hot water, cooking and lighting and the grid becomes unreliable, your home becomes a very difficult and uncomfortable place to live. There are also issues over the reliability of supply chains for spare parts and technical expertise for maintenance. These would apply even if you had your own off-grid generation.

So, should we be thinking about building resilience into our homes and other buildings, even if it means additional cost, or can we rely on the services and systems we all take for granted to always be there?

Underfloor heating and flooring advice sought

gingernut — Thu, 15 Nov 2007 01:07:50 +0000

Wondering about putting in underfloor heating to heat my kitchen, which is in basement. The existing floor is concrete but is very dusty and worn into hollows in places, also some damp coming through... What would be the best way to proceed?
From talking to friends - suggestions include - A.building new floor on top of existing (there is room to raise floor level by 200 mm) or B. Dig out floor with jackhammer and lay new floor to existing level.
A. sounds easier, but can see that timbers ( including the stairs ) would have to be removed below new floor level, plus door , but this needs replacing anyway.
I would like to use a lime-crete floor if possible.
Hope this is rpeating a question already covered elsewhere
Thanks

Cavity wall insulation

spah — Mon, 14 Jan 2008 16:46:07 +0000

We have been considering cavity wall insulation for our semi-detached edwardian house. It has some insulation where we have had extension work but there is a large expose flank wall and rear wall.

We have talked to local installers who use foam or fibre but we have been advised by a local surveyor architect to look for perlite or silalite beads. This was partly because we do have a problem of rats in the locality and they cannot burrow through theis loose bead insulation. Thus wool fibre etc will not be any good.

However finding a contractor seems more difficult. we live in Southampton and wondered whether anyone had suggestions for local contractors who install loose bead insulation.

Retaining wall and drainage installation - Specialists builders required?

kipper — Wed, 16 Jan 2008 14:11:03 +0000

Hi,

Around 2 years ago we purchased a converted barn. After moving into the property we became aware that we may have a damp problem as the wooden floor we had laid began to lift and two of the rooms smelt musty. The rear of the property is built into a bank.

We pursued the organisation who provided the morgage and survey who admitted to not testing for damp in all walls and eventually admitted there is a damp problem present as well as a number of other issues not raised by the survey.

We have had a number of specifications of works provided by various damp proofing companies, surveyors etc. proposing different ways of dealing with the damp.

I have enclosed a specification below provided by a member of the British Structural Waterproofing Association (BWPDA) which I beleive is the best specification provided as they propose to remove the soil off the wall and run the water goods into existing draining at the front of the property which has been approved by building control. This is also the most expensive proposal.

"Summary

In order to prevent lateral penetration of dampness through the rear wall, we would recommend that external measures are carried out prior to any internal remedial damp proofing. This would be achieved through the reduction of the external ground level, construction of a gravity retaining wall, a topside gulley to divert field run off, installation of land drainage and soak away to remove water from the side of the house and deal with water from rainwater goods. The soakaway will be run through the garage to the front of the property and either connected to existing drainage (if combined foul and rain water drainage) or run into the front pond.
We are assuming that the construction of the external wall is suitable for external ground level reduction, the excess removed spoil will be disposed of within 40m of the property
Proposal outline
1. Conduct site survey and prepare site plans and detailed design specification, including locating services running through driveway
2. Remove existing fence and erect safety barrier.
3. Excavate ground from side of property to leave passage between bottom edge of retaining and the property. Target depth is to give a finished ground levell50mm below internal solid floor level, foundations permitting, as per attached schematic
4. Construct gravity retaining wall on 1:8 batter using 225mm concrete blocks on edge
5. Grade surrounding ground to facilitate run off from fields.
6. Install perforated land drainage pipe work in the newly formed area between the house and the retaining wall, connected to a soakaway.
7. Run soak way drainage through garage floor to front of property and connect either to existing foul/rainwater drainage or to pond. Connect existing guttering down pipes to this drainage.
8. Reduce external ground level to 150mm below kitchen floor in the patio area. 9. Install new stock proof fence
10. Remove construction waste from site and reseed excavated area."

My question is should we be focusing on using a:
specialist damp proofing company and paying a premium or
using seperate retaining wall and groundworks companys or
Using a general building company?

I have inserted some links below to images showing the current drainage and rear of the property. Please let me know if these cannot be accessed.

http://i44.photobucket.com/albums/f44/kipper1/House/IMG_2141.jpg
http://i44.photobucket.com/albums/f44/kipper1/House/IMG_2385_1.jpg
http://i44.photobucket.com/albums/f44/kipper1/House/IMG_2138.jpg
http://i44.photobucket.com/albums/f44/kipper1/House/IMG_2136.jpg

Thanks,

Chris.

Lifetime Homes Standards rewritten?

Peter A — Thu, 17 Jan 2008 10:01:15 +0000

Has anybody heard anything about the Lifetime Homes Standards that government are getting rewritten, I assume this is ahead of Lifetime Homes becoming a mandatory section of CSH as threatened for 2010?
I guess they will try them out ahead of this when certifying code submissions.

Are the UK Governments 2050 Cabon Emission Targets achievable?

happyadd — Sat, 12 Jan 2008 18:40:05 +0000

Hi;

I am a final year student studying Quantity Surveying at the University of Glamorgan, Wales, UK.

For my final year dissertation I have set a question which asks whether the UK Governments CO2 reduction targets are achievable at present within the UK Construction Industry.

However, as part of my research I have proposed a questionnaire that targets the areas which I feel most contribute to achieving the targets.

I was hoping you guys may be interested in taking part. It will be used completely anonimously and will be in the format of an excel spreadsheet where you can tick the boxes and send it back.

If you would like to take part please contact me at happyadd@hotmail.com
and I will send you a questionnaire.
Your contribution would be greatly appreciated.

Thank you so much for your time

Adam

BecoWallform

James Norton — Tue, 15 Jan 2008 20:08:57 +0000

Was recently looking on the http://www.passivhaus.org.uk/ website and noted the following two accredited systems:

http://www.becowallform.co.uk/web/wallform.html
www.wolf-passivehomes.com

Both use insulated concrete formwork, ie, in section, from inside to out, about 50 EPS type material, 150 reinforced concrete, 200ish EPS. Question is how would this perform in terms of thermal mass, clearly the concrete is insulated from incident radiation but the mass is still much nearer inside than out so some storage must occur...?

Any thoughts / experience would be appreciated...

(would be interested in knowledge on cost, reliability etc as well as performance...)

J

Passive summer ventilation

stephendv — Mon, 14 Jan 2008 18:00:31 +0000

I plan to use an MVHR during winter, but would prefer to make use of some passive ventilation during the summer. Our new build design has a double storey vaulted ceiling in the living room with the rest of the house being open plan, so the best location for a warm air escape vent would be towards the top of the roof. Now the dilemma:
- since the ventilation should only be provided in summer I'd like to be able to close it during winter and still have excellent insulation in the roof.
- also, there should be minimal solar heat gain through the vent during summer.
For these two reasons I'm not keen on using skylights since they fail on both counts.

Does anyone know of suitable products or techniques which can be used for this?

Air permeability and air changes - What is the difference?

steveleigh — Mon, 14 Jan 2008 09:55:33 +0000

Some people seem to be confusing the air permeability of a building envelope with the air changes of a building envelope.

The air permeability of an envelope measures the build quality of the envelope. Air permeability means uncontrolled air leakage through cracks and fissures (even microscopic cracks will leak air) in walls and roof.

Air changes per hour measures the ventilation of the building. This can be controlled by a MVHR (mechanical ventilation heat recovery) passive ventilation or simply opening windows and doors.

AECB gold standard is 0.75.m3/m2hr@50Pa but if air permeability can be reduced to 0.25 m3/m2hr @50Pa or even zero (which I think is quite achievable with a sealed system) this will dramatically increase the performance of insulation and improve the durability of all structural materials.

Cheers Steve

Domestic Energy Assessor

ekoshack — Sun, 10 Jun 2007 18:38:11 +0100

Hi, i am considering a new career as a domestic energy assessor, however i have a few reservations before i take the plunge. My previous experience has been as a nurse and latterly as an assistant at a special needs school and i am a little concerned about the geeky and scientific aspect of the course, will i be able to cope? My only advantage is that i have helped to project manage 3 self build properties with my husband. My other problem is choosing a training provider, there are various training providers ranging from Â£1400.00 to Â£4500.00 for a 8-10 day course, all of which seem to follow the VRQ Lvl 3 syllabus. Finally given the public reaction to HIP and all certificates that comprise said pack i am a little sceptical about future employment Vs my investment. Personnaly i think this is a step forward for both buyers and sellers if the concept is implemented correctly. So to my questions, can anyone reccomend a training provider, allay my fears over future employment and advise me on courses content.

Ta

Eko shack

replacing glazing but saving frames?

chocolatepixie — Sun, 13 Jan 2008 14:52:58 +0000

I have a bay window with single glazing. According to Haynes Eco House Manual it is possible to replace single glazing in timber structures such as bay windows with double glazing without replacing the frame. Does anyone have any experience of this or any thoughts on it?

Extracting heat from roof tiles

workaholic — Fri, 30 Nov 2007 08:55:56 +0000

Does anybody know of a system that can be used to extract the heat from roof tiles.
I spent most of the summer laying thousands of tiles on my roof and they get really hot in the sun. I was planning to put pipework under the tiles to extract this heat. Unfortunately I got the tiles on, but not the pipes. The reason being that I could not think of a way, at the time, to get a good thermal contact with the underside of the tiles. I did not think that the pipes would absorb enough heat just fixed in the space below the tiles. Why are UFH pipes always white, surely black would be better?
The best idea I have thought of is using a system similar to the old Finrad heating pipes. These were 22mm pipes covered with very thin aluminium fins. The fins were so thin you could flatten them with your fingers. You could lay something like this under the tiles and then the tiles would deform the fins as they were laid and be in contact with them.
Anybody have any ideas?

roof pricing

huercalovera1 — Sun, 13 Jan 2008 22:00:52 +0000

Just looking for a rough price (labour only) to strip, re-felt, batten out ,then re-tile 220m2 of roof(marley double roman),also to felt,batten out 6 dormer roofs(plain tiles) to be tiled sides and front ,using corner tiles. All hips and ridges to be dry using marley system, a rough price would be appreciated ,so that I have something to work on. Thanks.I estimate approx. 3-4 weeks work.

Air source HP & Immersion heaters?

Paul @ Carbon Free — Thu, 10 Jan 2008 16:03:30 +0000

Hi Guys,

I'm looking at the possibility of installing an air source heat pump (Viessmann AWO 110) in a new build property with a single phase electricity supply and a heat demand of 12kW. The AWO 110 has a heating output of 9.3kW with a power consumption of 3kW, therefore a COP of 3.1 at an operating point of 2 degree's air temperature to 35 degree's water temperature. The property will be inhabited by two occupants and so DHW heat requirement is 0.5kW (presuming there is no solar yield, therefore worse case) which means I need to achieve an output of 12.5kw.

In order to get to the 12.5kW output I'll need to use a 3kW Immersion heater as a weather compensated 2nd heat source in the buffer vessel, and in addition to the heat pump and the solar heating for the DHW (Vitocell B-300 twin coil cylinder) I would like to install another 3kW immersion here in order to activate periodically to eliminate any risk of legionella.

This means I'll have a maximum power requirement of 9kW and as I'm not an electrician I'm concerned the heating system could be pulling too many amps?

If anyone can explain the In's and out's of how much power I can pull from a single phase supply it would be very much appreciated.

Kind regards

Paul

Ground source heat pump question

mikejd — Thu, 22 Nov 2007 15:21:58 +0000

I have installed a ground source heat pump in the house I am renovating in Aberdeenshire. This was commissioned last week and is operating at a low temperature for the first week or two. The house is very warm so it is working OK but I am a little concerned about ice formation on the ground loop pipes. I have raised this with the pump supplier who assures me it is OK and will settle down, but I would still like to get any comments from anyone who has installed one.

Initially the ice began to form on the return pipe from the heat pump to the ground loop (which is a borehole) after a day. By the third day the flow pipe was also icing up. The pump unit has a GL return temperature reading of -3.4deg, it doesn't show the incoming temp. The heating side temperature is between 31 and 34deg. The suppliers said it was because the house was not completely weathertight and the pump was working hard but this has now been sorted and the ice is still there.

Is this something I should be concerned about? Will the ice disappear eventually or will it always be there?

Any comments appreciated.
Mike

UFH - but how to power it?

dnfh — Thu, 10 Jan 2008 23:21:43 +0000

I like UFH (warmish feet, cool head, no radiators to damage antique furniture etc), but am getting very confused on how to power it. I would be very grateful for the wisdom of the experts!

c. 6kW heating needed, + c. 2kW HW. Old house so may be too leaky for HRV to be worthwhile (abut to be tested). Insulated about as well as possible.
UFH Heating:
Initial plan was ASHP 'cos of COP 3 etc, but as gas is 4x cheaper a new boiler might be better? There used to be gas fridges (at least for caravans etc). Would a gas ASHP - if it exists - be the answer?
If we could provide the electricity ourselves then ASHP would be great. No hydro, wind dubious (site considerations and Conservation area) and PV limited and V. expensive (but may be useful in 5 yrs?).
microCHP. Apparently for a small increase in gas will proivde effectively free electricity - ? 2kW
wood pellet boiler? Don't know much about them.

HW: solar probably, but top-up with what?
Gas boiler is easy.
Could use another ASHP with lower COP for 50oC HW, but still electricity problem.

Any thoughts?

The PassivHaus Planning Package (PHPP) - Any good ??

James Norton — Sat, 12 Jan 2008 21:14:56 +0000

Has any body used this software, is the price tag worth it or could just look to free stuff like Paul's Canadian Hot2000 etc..?

J

Research Paper on AECB Enery Performance Standards

drjonnyc — Thu, 10 Jan 2008 22:21:37 +0000

Hello,

Well this is my first discussion and post!

I am currently at the beginnings of my dissertation for university - a long research process!

The topic that i am looking at is the AECB Energy Performace standards - and the cost implications that each level (Silver, PassivHaus, & Gold) bring.

The research that i have conducted so far informs me that the silver standard can be achieved will practically no extra cost, but i have not found anything relating to the PassivHaus & Gold standard.

I would apprciate any help on the subject in particular background to costings of the 3 levels.

Thanks

BREEAM: Does it make a difference or is it just a paper trail?

drjonnyc — Fri, 11 Jan 2008 22:27:10 +0000

As a main contractor we are working on more and more projects that are enrolled in the BREEAM standard. Depending on the rating required, all i seem to be doing to ahieve the required points is producing paperwork. Does having a project enrolled in the BREEAM standard actually make a big difference or is it more of a red tape exercise?

How cool should a house get?

tony — Sun, 23 Sep 2007 00:17:19 +0100

Typical Victorian terraced house rarely falls below 14 even in winter

A 1970/80's timber-framed house regularly gets below 7 by the morning in winter without the heating on

Is there any case for heating unoccupied houses? Or occupied ones at night?

How cold should a house be allowed to get?

How thermally stable should a home be designed to be or doesn't it matter?

hard landscaping

dougstrachan — Wed, 09 Jan 2008 12:59:40 +0000

Does anyone have any ideas for an environmentally sound method of providing hard landscaping, particularly for off street car parking in a domestic setting?

closing crawl space and VOC

mbartosik — Wed, 09 Jan 2008 23:35:48 +0000

hi, this is my first post. I'm a Brit in New York, and getting close to net zero energy for my 1963 house.
As part of my project I've closed a crawl space.

Here is what I've done:
Close crawl space vents.
Insulate crawl space walls with 2" R10 foam board (will add one more layer later).
Covered dirt floor with plastic.

Now here's my problem, rather than using 6 mil polythene to cover the dirt floor, I was bothered of tears, so I put down a pool mat and then a 20 mil pool liner. The trouble is that the pool liner is vinyl and off gases.

So to avoid the off gassing I could:
1) Rip out the vinyl liner and replace with polyethene? -- a big waste, and I've glued it to the insulation (with low VOC glue)
2) Cover / seal liner with a layer of polyethene.
3) Cover liner with thin concrete slab (I only have 24" height, so a max 2" slab / cap)
4) Vent the crawl space using the energy recovery ventilator that I already have (just fit an extra 4" duct).
5) Combination of above.
6) Wait and hope that off gassing reduces.

I could do a combination, like 2 then 3, and 4.

If I add a thin concrete slab (it does not need to take a load) then how thin could I get away with, and how thick insulation should I use under it. I'm thinking about 1.5" of concrete with some re-enforcing. Remember I've only got 24" total height.

Any advice please??

FYI: to get to net zero, so far I have 13KW of PV, 2 stage ground source heat pump, window upgrades next month (www.apleninc.com - mostly fiber glass), upgraded insulation, still to replace doors, and insulate basement. So far I'm able to cover my energy usage for 10 out of 12 months including heating. Also crawlspaces.org is useful for tips.

Free RETScreen Clean Energy Project Analysis Course Jan 30th Uxbridge

Paul in Montreal — Thu, 10 Jan 2008 13:50:28 +0000

Le franÃ§ais suit...

Energy Efficiency & RETScreen Version 4

Engineers, architects, technologists, planners, facility managers and
educators are invited to a free RETScreen Version 4 introductory training
seminar. The seminar is intended for these and other professionals who
would like to learn how to use the RETScreen Clean Energy Project Analysis
Software to assess the viability of energy efficiency measures for
commercial, institutional and residential buildings, and for industrial
facilities. Registration will be on a first-come-first-serve basis. Click on
the events below for details and to register online:

- Montreal, QC, Canada â€“ January 15, 2008
- Gatineau, QC, Canada â€“ January 22, 2008 (French)

-> Uxbridge, Middlesex, UK â€“ January 30, 2008 <-

- New Delhi, India â€“ February 7, 2008
- Washington, DC, USA â€“ March 3, 2008

Each seminar will provide a basic overview of RETScreen Version 4, including
its applicability for various clean power, heating and cooling technologies.
The participants will then see a demonstration of the new energy efficiency
model and learn how to use the software to evaluate existing or expected
energy use, assess potential savings opportunities and then prepare proper
financial analysis for stand alone measures and entire facilities as a
system.

The RETScreen Software, available free-of-charge, is now being used by more
than 134,000 people in 222 countries and this is growing at more than 900
new users every week. RETScreen is quickly becoming the international
standard for clean energy project analysis.

Please feel free to forward this e-mail to colleagues who would be
interested in attending one of these seminars.
______________________________________________

EfficacitÃ© Ã©nergÃ©tique et RETScreen Version 4

IngÃ©nieurs, architectes, technologues, planificateurs, gestionnaires
dâ€™installations et Ã©ducateurs sont invitÃ©s Ã un sÃ©minaire
dâ€™introduction Ã la version 4 de RETScreen, offert gratuitement. Ce
sÃ©minaire cible ces professionnels, et autres, intÃ©ressÃ©s Ã apprendre
comment utiliser le logiciel dâ€™analyse de projets dâ€™Ã©nergies propres
RETScreen afin dâ€™Ã©valuer la viabilitÃ© de mesures dâ€™efficacitÃ©
Ã©nergÃ©tique pour des bÃ¢timents commerciaux, institutionnels et
rÃ©sidentiels, ainsi que pour des installations industrielles.
Lâ€™inscription se fera sur la base du premier arrivÃ©, premier servi.
Cliquez sur les Ã©vÃ©nements ci-bas pour plus de dÃ©tails et pour vous
inscrire en ligne :

- MontrÃ©al, QC, Canada â€“ 15 janvier 2008 (en anglais)
- Gatineau, QC, Canada â€“ 22 janvier 2008
- Uxbridge, Middlesex, UK â€“ 30 janvier 2008 (en anglais)
- New Delhi, Inde â€“ 7 fÃ©vrier 2008 (en anglais)
- Washington, DC, Ã‰.-U. â€“ 3 mars 2008 (en anglais)

Chaque sÃ©minaire offrira une vue dâ€™ensemble de la Version 4 de RETScreen,
incluant son applicabilitÃ© Ã diverses technologies dâ€™Ã©nergies propres
pour la production d'Ã©lectricitÃ©, de chaleur et de froid. Les participants
pourront ensuite voir une dÃ©monstration du nouveau modÃ¨le dâ€™efficacitÃ©
Ã©nergÃ©tique et apprendront comment utiliser le logiciel pour Ã©valuer
lâ€™utilisation existante ou prÃ©vue de lâ€™Ã©nergie, dÃ©terminer le
potentiel des opportunitÃ©s dâ€™Ã©conomies et prÃ©parer une analyse
financiÃ¨re pour lâ€™Ã©valuation dâ€™une seule mesure dans un Ã©tablissement
ou pour lâ€™Ã©valuation de l'Ã©tablissement dans son ensemble, en appliquant
plusieurs mesures et considÃ©rant lâ€™Ã©tablissement comme un systÃ¨me.

Le logiciel RETScreen, disponible gratuitement, est maintenant utilisÃ© par
plus de 134 000 personnes rÃ©parties dans 222 pays et auxquels sâ€™ajoutent
900 nouveaux usagers chaque semaine. RETScreen devient rapidement le
standard international pour les analyses de projets dâ€™Ã©nergies propres.

Nâ€™hÃ©sitez pas Ã transmettre ce courriel Ã vos collÃ¨gues qui seraient
aussi intÃ©ressÃ©s Ã participer Ã lâ€™un de ces sÃ©minaires.
______________________________________________

RETScreen International
Clean Energy Decision Support Centre
Centre d'aide Ã la dÃ©cision sur les Ã©nergies propres

Natural Resources Canada - Ressources naturelles Canada
CANMET Energy Technology Centre - Varennes
Centre de la technologie de l'Ã©nergie de CANMET - Varennes
1615, Lionel-Boulet, Varennes, QC J3X 1S6, Canada
E-Mail - Courriel : rets@nrcan.gc.ca

Website - Site Web : http://www.retscreen.net

SMA GRID TIE INVERTER

greenerenergy4u — Thu, 10 Jan 2008 10:05:35 +0000

HELLO ALL,
I AM LOOKING TO BUY A SECOND HAND SMA WINDY BOY INVERTER.
I WOULD BE INTERESTED IN ANY SIZE BUT PREFERABLY 2.5KW.
THANKS
MICHAEL

Air to water heat pumps

pbj — Mon, 07 Jan 2008 14:17:43 +0000

We are considering the use of the above for some new social housing development within the Teignbridge area.
Any feedback on operational issues, particularly at low ambient temperatures, running costs, corrosion problems in coastal areas, internal space for HWS components, etc. would be most welcome.

Bedroom ventilation

Joatex — Wed, 02 Jan 2008 15:14:59 +0000

Given the following parameters, a small bedroom, single occupant, cold nights so window (Velux)shut, bedroom door shut for privacy, how does one manage two air changes an hour ? Vents top and bottom of the door or though the wall next the corridor? Draught under the door? Ideas welcome.

Code 5 upgrade and MVHR unit in exchange for 2 years monitoring

steveleigh — Wed, 02 Jan 2008 13:15:32 +0000

My company and RoofKrete Ltd would like to offer to install our airtight thermal cladding system on a suitable existing building (old or new) in return for allowing full monitoring access for at least two years as part of a project.
This would need to be completed during the first quarter of 2008. We would supply and install an exterior insulated render system complete with valves to monitor airtightness including a new insulated roof to provide a maintainable sealed system and we would also provide a MVHR unit FOC.

We have a thermal render system which has been installed, over a period of twelve years, as a monolithic membrane (without joints) over thousands of buildings as watertight protection. This system could now be easily adapted to encapsulate a full building as an airtight external thermal cladding system.

The figures we hope to improve upon with this system are as follows:

Air permeability 0.25 m3/m2hr @50Pa.

Thermal bridges 0.1% of wall and roof area.

Wall and roof aggregate U-Value 0.10 W/m2K

We have focused our attention on the major weakness of UK building envelopes, air permeability. Most building envelopes will eventually develop air leaks through thousands of tiny fissures and cracks and connections between roofs and walls. Air infiltration can be eliminated by a render system which does not develop unseen fissures and cracks but forms an airtight seal which effectively separates the internal atmosphere from the external atmosphere.

The Canadians have already attempted to seal buildings during the seventies and eighties and failed because of the inability of render systems to remain airtight. The principle of a sealed building envelope is a sound one because it increases the performance of insulation by as much as 50% and allows building control systems to operate effectively giving the occupants complete control over every fraction of heating or cooling energy regardless of the outdoor climate.

Our Code 5 Upgrade Project will have no reliance on Government funds in the form of research and development grants and it will be commercially viable (without any form of subsidy) on the social housing market. It will satisfy stringent environmental and sustainable construction requirements.

We have had a lot of interest from housing associations and we are due to start our first new homes in the second quarter of 2008. However, we would like an environmentalist as an occupant to monitor a building over a two year period. If you have a house which is suitable for upgrading and would like to be involved more details can be found at: http://www.sustainconstruction.com/TC_Project.html or email me at RoofKreteTC@sustainconstruction.com.

We are confident that we can achieve a code 5 CSH envelope at no extra cost over present new building costs

Cheers

Steve

Flat Pack Yurts - Your opinions?

Snitcherwitcher — Thu, 20 Dec 2007 09:39:15 +0000

Hi - I'm wondering what you think about pre fab Yurts - specifically from places like yurtworks.com

I appricate that although they are a tradional, ethnic design - this company is based in the US (so lots of transport miles), however once built - my idea is to run them off the grid with the aid of solar and wind, a wood burning stove and boiler. Also straw bale walls placed internally and lime plaster and possibly a grey water system.

Firstly what do you think about the products?

and do the green features Im hoping to install out weight the miles it will of travelled originally?
(I think so - Consider that the Scampi you buy in super markets has been shipped to Thailand and back just to be peeled! - Its friendly than getting a machine to do it here! - apparently)

Parge coating to improve airtightness

Pingy — Tue, 08 Jan 2008 09:05:37 +0000

Is it worth applying a parge coat to the inside of a solid 9" brick wall prior to building a new block wall on the inside to create a cavity wall?

My thinking is that although the new block wall will be wet plastered and therefore hopefully airtight, the cavity in which the insulation will be located may not be so airtight (using mineral wool batts for insulation). Would re-pointing the external lime mortared wall be just as good at making the cavity airtight?

Masonite beam construction

dickster — Mon, 07 Jan 2008 10:36:54 +0000

Hello, start building small bungalow next year. Our architect has come up with a design with floors, walls and roof made out of masonite beams and infilled with recycled paper. All very eco and seems just what we want.

Has anybody had any experience with this type of construction, good or (more importantly) bad?

Roof feature - Heat Island Effect

GBP-Keith — Sat, 11 Aug 2007 09:36:14 +0100

I'm minded to believe that the thin sedum green roofs that are becoming common in the UK would be less able to reduce the heat island effect than deep planted grass roofs that are more common on the continent. Does anyone have an opinion on this or know of any research that support or dispels my theory?

Stone walls and impermeability

dnfh — Mon, 31 Dec 2007 20:13:54 +0000

We have bought a 1770 2 storey stone walled house. Curiously in 1996 permission was given fand the first floor was dry-lined with standard plasterboard with c. 50cm air gap - and vinyl paint. The ground floor was directly plastered with modern cement plaster (NOT lime). Over the last 3 months neither first nor ground floor has any damp detectable (first floor in the air gap, ground floor directly meassured with probe meter).
Neither floor has any formal insulation, and we wish to improve the heat loss to allow heating with Air source heat pump and thus reduce our carbon footprint. While generally wishing to follow green principles, these have already been breached with no apparent problems. This poses two questions.

1. Ground floor: As it has already been impermeable for 10 years without apparent problem, is there any reason not to put eg urethane foam on top of the plaster?

2. First floor: If (again) standard plasterboard has been fine for 10 years, we can presumably put standard insulation on top of the plasterboard. But would putting urethane foam IN the cavity produce problems despite the apparent lack of current problems?

(Urethane seems to be much cheaper AND more effective than eg cellulose).