Green Building Forum - All Discussions

MVHR efficiency meamsurement reliability

wholaa — Wed, 17 Jul 2024 12:56:02 +0100

Hi all,

I have noticed there is a seeming discrepancy between MVHR efficiency listed on the passive house portal and what is described on manufacture specifications. For example, the Zehnder Q600 is regarded as high end and is passive approved and listed as having 87% heat recovery efficiency. The Vent-Axia Sentinels which are not passive approved are listed as 91% efficient. Has anyone explored this topic in detail?

Honeywell fan problem

djh — Fri, 19 Jul 2024 18:07:06 +0100

We have a Honeywell QuietSet oscillating tower fan (HYF290E) that is normally kept in its box, but today I took it out :bigsmile: When I turned it on, as well as the normal "quiet" fan & air noise I can hear a regular thumping noise. Quite a soft noise but loud enough to be annoying. Maybe once or twice a second thump, regardless of whether the fan is oscillating or not. It does vary with fan speed though. The thump is at the lowest speed. At higher speeds there more of a hum, but at the highest speed and at one speed in the middle of the range the extra noise seems to disappear completely.

Any thoughts what the problem is? I'll dismantle the fan after dinner and hope to resolve it then, but I hoped somebody might have a suggestion as to what it is. Entertaining or useful suggestions welcome!

Water main replacement

Artiglio — Wed, 10 Jul 2024 21:52:31 +0100

Evening all

Anyone have any input for the following.

My place was connected to town gas and mains water around 1935, both were run in “water barrel” steel/iron pipe.
Same trench about 4 inches apart and buried about 500mm max ( it’s around 400mm nearer the point it enters the building) Later the gas was rerun by passing aplastic pipe through the old gas pipe and a water meter fitted.
There’s a weep in the incoming water pipe close to where it enters the house and ideally it all needs replacing back to the meter. However the existing burial depth and proximity to the gas make it all rather problematic.

If it follows the same route going down to 750mm risks going below the footings ( old barn spread brick off of chalk) plus gas pipe is very close.
I’ve dug down in 4 spots and located the gas and water pipes.( both are parallel to and within 400mm of the wall. Water pipe seems to be bitumen coated and in fair condition given its age.
A little wary of calling out waterboard just in case it opens a can of worms regarding proximity of the gas along with the shallow burial depth of the existing.
I’ve located a joint in the pipe , what are the chances of that undoing with a bit of heat and gentle persuasion? ( i could then connect a plastic pipe and run it into the house ( i’ve installed a duct to the correct depth for the entry point ))
Has anyone any recent dealings with gas/water utilities ? If so what sort of response have you had? It wouldn’t be impossible to reroute both in a loop away from the building and back in , but a huge amount of work i’d really rather not do at this point , plus no idea as to what costs i could be liable for from gas and water board ( trench within my boundary i can deal with).

Underfloor heating upstairs....

Victorianeco — Mon, 08 Jul 2024 18:10:21 +0100

Finished floor coverings removed, looking at installing UFH upstairs.

Has anyone done a cost to benefit calculation on various methods?

I'm thinking:

A. 50mm PIR insulation between joists sat on roof batten, 16mm pipe in a 50mm biscuit screed (potential issues for weight?)

B. Spreader plates with rockwool insulation below

C. Any other alternatives whilst the boards are up?

We have approximately 100m2 of upstairs floor area to do. Finished floors will be 18mm OSB with underlay and carpet...

leftovers

jms452 — Mon, 15 Jul 2024 08:41:48 +0100

I have the following that needs clearing out following a project.
Location: Royston near Cambridge

2x 100m Pavaflex batts plus off cuts:
https://www.wickes.co.uk/Pavaflex-Flexible-Woodfibre-Batts---1220-x-575-x-100mm---Pack-of-4/p/287714

half a roll of breather membrane:
https://www.wickes.co.uk/IKO-Rubershield-Eco-Extra-120g-sqm-Breather-Membrane---50-x-1m/p/253810

150mm round MVHR ducting 2m long

204x60mm rectangular mvrh ductng 2m long

Various MVHR ridid connectors 150 & 125mm round, 204 x 60 rectangular

let me know if anyone can put to good use.

Whole house refurb project - Where to begin?

Victorianeco — Fri, 14 Jun 2024 21:30:08 +0100

Property is a detached 5 bedroom 1960's build on the seafront in South Wales

Current spec. appears to be:
- 24mm DGU's, ~20-25 years old, numerous failed units
- Cavity wall - unsure if insulated
- Loft insulation ~250mm mineral wool
- Heating is a gas system boiler, gravity fed tank system with single radiators in every room
- Ground floor uninsulated

We would like to upgrade a lot of things and add a rear single storey extension but just wondering the best order to plan this project as we are also living in it?

On our list in a rough (what I think) order;
- Cavity insulation if not done so (EPS beads) any grants available?
- Insulate heating cylinder and lag pipework
- Installation of ASHP and cylinder - keep gas for now also?
- Take up ground floor, insulate and install wet UFH
- Remove all upstairs rads?
- Open up existing window openings for new designs/layout (assume EPS beads will stay in place being the newer glued type?)
- Install double/triple windows faced on outside skin
- EWI to front elevation
- Rear extension (block on flat with EWI) and knockthrough
- Double/triple glazing to rear and side elevations
- EWI to rear and side elevations
- Replacement roof with solar panels (South facing)

We need to do it in phases as we're going to be living here and we are also in no rush financially or stress wise to jump all in

What experiences do people have they can share? Or would you do the above in a different order perhaps? Maybe jump straight into the roof work to take advantage of solar power etc?

Thoughts appreciated

House link:
https://drive.google.com/file/d/1B-VpHGUqUlascnhMbsdKpxQxifg7WSUV/view?usp=drivesdk

Damage from neighbours tanking years down the line

just_breathe — Mon, 25 Mar 2024 17:58:44 +0000

Hi

I’m convinced either our neighbours shower is leaking water or we have damp in our basement party wall (no where else!) caused by our neighbour (end terrace up hill).

He insists the shower isn’t leaking but last time I got a sneaky look in his basement plasterboard was hanging down.

But he also says things like there’s an underground stream - I dug out our concrete floor and removed all cement from walls and as my username suggest, used glapor, limestone flags, cork and lime hemp. No where else is damp and I’m gutted he won’t try to find the issue as don’t want to fall out.

What are my rights, I know it’s prob not coming from ground as rest of basement is dry, so in the cavity in our rear extension which is ground levels above basement - surely I’d see condensation?

Help appreciated!!

Insulating the eves of a hipped pyramid roof

Huwblut — Tue, 02 Jul 2024 16:23:00 +0100

Hi again everyone

I’m still plugging away with my little bungalow project. Following on from my post about insulation I’m now trying to figure out how to get it into the eves but still leave a 50mm gap for ventilation.

I’ve manage to get a photo downloaded so I hope that it helps. There’s lots more photos which I’m sure would be really useful but I can’t seem to get more that one in…

I’m told that it’s a hipped roof in the shape of a pyramid. It’s got two little bays at the front.

The corners are of particular concern as it’s a real junction of timber! There was some insulation in there previously but it was patchy which left cold spots and which resulted in some condensation / mould.

The ceilings are down and there’s access from above and below. I’ll be insulating the main body of the ceiling / floor from underneath.

I’ve been looking Manthorpe Refurb Eaves Panels:

https://www.manthorpebp.co.uk/roofing/roofspace-ventilation/refurb-eaves-panel-0

but the irregular spacing of the joists and rafters make it difficult.

I’ve also been looking at their eves ventilation roll:

https://www.manthorpebp.co.uk/roofing/roof-ventilation-%E2%80%93-solutions-modern-day-problem/roll-panel-vents-1

which may do a job as well.

I’m wondering if all the roof needs a 50mm gap or could I compromise and do as much as I can do and hope that there’ll still be enough air movement?

All the soffits will be replaced as well so I could include some extra ventilation there.

Apologies if I’ve not explained this too well.

I’d be lost without the help of the forum!

Cheers

Huw

Breathable floor with VCL - any point

Peter_in_Hungary — Sun, 30 Jun 2024 15:16:02 +0100

I have a friend with an old stone house. Minimum founds. and of course no DPC.

As bought it has concrete floors.

An 'eco friendly' architect is recommending removing the concrete floors and replacing them with something vapour open. There are no problems with the walls or plastering despite concrete floors for about 50 years.

Their plan is to replace the floors as recommended and then they want to put down engineered wood or click fit flooring (budget dependant) However all the instructions for the various flooring require a VCL under the flooring otherwise the guarantee is void.

Question - is it worth digging out the floors for something breathable only to put a VCL under the engineered wood or click fit flooring?

PV plus wood burner system: thermal store or vented?

EshanessAl — Thu, 20 Jun 2024 20:12:54 +0100

Hi folks. I’d like to pick your brains on a system for our small 2 bed croft house. We currently have an old Rayburn we are switching for a more efficient boiler cook stove. It’s our main cooker so on every day in winter but not so much in summer. We have 4kW PV but soon will have 7kW with a battery and diverter to immersion. The new stove will output 9kW to water. Currently got a bath and will add a shower. We just need 2 rads.

I can’t decide between a thermal store or vented cylinder. We can only fit about 150L cylinder and have very little head for pressure on a vented system. No radiators yet but planning either 2 radiators or low temperature in-wall heating (like underfloor but in the wall!). the benefit of the thermal store is that the PV could contribute to running the heating, which would be great, and be a good dump for summer days (we still need heating in summer). Plus nice to have mains pressure HW. Vented system would be simpler for plumbing, I’d probably use standard rads, and could add an electric radiator as a summer dump if needed. Shower would probably need a pump.

The stove is rated to work with an unvented system too so that is a possibility, just a bit put off by the fact it needs a registered installer and annual service.

Thermal store would be gledhill or advance appliances. Leaning towards AA as it works in a power cut, which we do get quite regularly in winter. Heard a few negatives on thermal stores needing to be maintained at high temp and dropping quickly with bath or heating. I don’t want to be topping it up from the grid if I can help it.

Thanks in advance!

bat survey requirement

lookseehear — Thu, 20 Jun 2024 18:24:24 +0100

Hello, we obtained planning permission for small extension and refurb works in April and no mention was made of bat roosting. We had already had a preliminary bat survey which showed no current activity but some evidence historically so recommended a further two surveys.

Where do we stand on what we actually have to do? I'm pretty comfortable we don't have bats in the loft spaces, but I'm aware that it's an offence to disturb roosting bats, and our works involves vaulting ceilings.

Code For Sustainable Homes - assessment for a dwelling?

gravelld — Mon, 24 Jun 2024 15:46:27 +0100

I'm looking at purchasing a house built to level 4 of the Code For Sustainable Homes in 2013/2014.

We're not at the stage of putting an offer in, and I realise I could ask the vendor, but I wondered if there was anywhere I could download the assessment for a given dwelling or group of dwellings?

I'm interested in how many "points" were scored for bike sheds etc as opposed to the truly useful things like fabric efficiency.

I haven't found an equivalent of the EPC register, and precious little about CFSH is mentioned in the original planning applications that were approved.

Installation of low profile shower tray on a concrete floor

Jeff B — Sun, 09 Jun 2024 12:57:05 +0100

I am replacing an existing tray because of my and my wife's advancing years. The one we have is on legs and consequently is quite high off the ground and my wife in particular is nervous of slipping and falling when exiting the shower. So we have gone for a large (1400 x 900mm) low profile tray to replace it. There are other consequential benefits as we will be using decorative PVC panels to cover the existing tiles (no more mouldy grout lines) and having a single sheet of glass (like a walk-in shower) so no doors with easier access and again no mouldy crevices associated with sliding doors!

We are in a bungalow with a concrete floor so by definition we have to excavate a channel in the concrete in which to site the trap and pipework to connect to the 110mm main drain. This has all been done (see photo). My dilemma (and almost paranoia the more I think about it) is what happens if any of the joints leak once the tray is stuck in place as there will be no way of telling if this occurs unlike with the elevated tray we had before.

A thought I had, because the tray will be stuck to the floor with adhesive and sealed all around the edges with silicone, is to simply drill a hole in the side of the 110mm pipe to allow any water to trickle down therein. There would not be a smell issue because the tray is effectively “hermetically” sealed over the drain.

I just wondered if anyone else has come across this issue or has any ideas of how to allay my fears!

Would you lime plaster interior walls too?

bgasparotto — Thu, 13 Jun 2024 14:39:43 +0100

Hey folks!

Carrying on with our 1910's Victorian style end terrace renovation we are installing wood-fibre for IWI and plastering the internal side of exterior walls with lime for the sake of breathability.

However, would it be advised against using a cheaper gypsum plaster on interior walls? We have a long-ish hallway that sits between the party wall and the other rooms of the house which is about 44m2 of wall surface. No damp issues so far and I just insulated the floor and guaranteed good air flow underneath on the about 80cm floor void. We don't expect moisture to be created on the space but it does lead to our kitchen and bathroom (both fitted with extractor fans).

These walls currently have the original lime after wallpapers removed. Should I do it with gypsum to save ourselves money and time or would we be shooting ourselves in the foot on the long term?

Here is the link of the image on the right orientation: https://ibb.co/x8xbB3J
Thanks,
Bruno

Insulating a service void

mattjcates — Mon, 10 Jun 2024 17:30:01 +0100

I am converting my loft with the following build up: 50mm ventilation gap, mineral wool between rafters then pir then vcl.
I am considering whether to use a 25mm service void for wiring to speed up installation and reduce the number of times the vcl is punctured. I am installing an mvhr.
I would be grateful for some views on the pros and cons of putting some insulation in the service void and if I do go down this route what material would be best.
Thanks!

insulation and ventilation in eaves

mattjcates — Tue, 11 Jun 2024 07:50:52 +0100

I am converting my pitched roof loft with 50mm ventilated gap, mineral wool between rafters and pir below then avcl.
I am installing an MVHR but recognise I will not be getting close to passive house standards on airtightness (retrofit, dot and dab plaster etc).
The original plan was to run the mineral wool and pir down to the corner of the eaves and be continuous with cavity wall insulation.
the problem is that trying to do the avcl detail in the corners is pretty much impossible because the space is so tight so I am planning to bring the avcl back to the ashlar walls.
Some of the MVHR ducting will be running in the eaves, it is insulated ducting and can be covered in plenty of mineral wool and we can tape the ducting entry points through the ashlar walls.
I am still interested in insulating the pitched roof down to the cavity walls which I think will help with temperature regulation in the eaves in both summer and winter but I'm now not sure about ventilation in the eaves! I'm a bit reluctant to use the pir in the eaves as this could trap moisture from living space below so I wonder about just using mineral wool between the rafters as a compromise.
Any thoughts!
thanks

Garden Equipment

Victorianeco — Wed, 29 May 2024 15:38:02 +0100

Looking for some garden equipment now I finally have a garden;

- Brushcutter / strimmer (rather have petrol than electric) - would be worth getting something commercial grade I think
- Pole saw and hedge trimmer
- Petrol mower

I don't think the battery ranges are worth their money / run time personally

Would also need some tools;

- secateurs
- lawn edging tools

Any other reccomendations?

Thanks

Cement recycling

Mike1 — Sat, 01 Jun 2024 12:36:14 +0100

This Cambridge Uni cement recycling invention looks to have great potential - https://www.cam.ac.uk/stories/cement-recycling

There's some more about the trials at https://cambridgeelectriccement.com/cambridge-electric-cement-industrial-scale-trial-launches-in-uk/

Patio and driveway cleaning and aftercare? sedum?

Victorianeco — Sun, 09 Jun 2024 10:10:33 +0100

We've just moved into our new forever home.

This week's project is cleaning up the block paving driveway and the concrete patio to rear.

So far I'm thinking:

- Spray all weeds with a white vinegar, salt and soap DIY spray
- Rake out by hand all weeds a few days later
- Jet wash
- Apply brick and patio cleaner (any recommendations on products?)
- Jet wash
- Dry and seal (any recommendations on products?)
- Fill all gaps with kiln dried sand

Would sedum be a good idea to throw into the gaps or is that just asking for trouble? We have plenty of grass elsewhere and bushes so I'm thinking a 'clean look' with no weeds or plants may be best for these areas?

We then also have a lot of crazy paving edges and dwarf walls.. Same process as above? What to repoint with iron completion? Do you need to seal up natural stone?

Optimal Hot Water Settings

Victorianeco — Sat, 01 Jun 2024 11:34:45 +0100

We have just moved into a 1960's detached property

Gravity fed system, gas sytem boiler and hot water cylinder (looks lightly insulated)

Am I right in syaing we should adjust the stat to 50c based on the top exit pipe temperature? Would you then heat it twice a day? Say 5am and 5pm? I have a FLIR camera I can base the temperature on?

The ultimate aim is to replace the system with an ASHP at a later date after insulation, windows etc. etc.

Thanks

Plumbing Rods

Rex — Tue, 04 Jun 2024 11:47:19 +0100

What ho one and all,

I have a small drainage issue and rather than digging up, it may be cured by plumbing rods (or a long drain snake.) Have never need rods before and as this is a kinda 'one off' job, don't want to spend much.

But there is quite a range of prices, anywhere from £20 upwards. What would I be getting with a more expensive set that I don't get with a £20 set.

The particular clearance job (roots?) does not require a lot of rod bending so the risk of breaking a rod is minimal.

Thanks and toodle pip

Water butts

Victorianeco — Sun, 02 Jun 2024 18:06:03 +0100

Any suggestion on water butts?

Where from, what size etc etc?

I would require one at the rear garden and one at the side to service the front garden.

Is the 210 litre set up sufficient for most use? I have square downpipes if that makes a difference

Eco Wood Treatment (ecowoodtreatment) - has anyone used it?

greenfinger — Mon, 03 Jun 2024 12:28:58 +0100

Hi

Has anyone used or come across:

https://ecowoodtreatment.com/

To begin with, I plan to use it on old fence posts and other timbers which I have re-purposed to make some firewood shelters. But in time I'm sure I'll find plenty of other uses if it's good...

Even if you haven't used it, any thoughts on its effectiveness from the info and claims on the website?

Many thanks

Guardian - Are energy performance certificates worth the paper they’re written on?

fostertom — Mon, 03 Jun 2024 10:36:36 +0100

https://www.theguardian.com/money/article/2024/jun/03/are-energy-performance-certificates-worth-the-paper-theyre-written-on
concentrates on downstream issues, barely mentions the fundamental shortcomings - skimpy guesswork in determining the construction as input, and perverse results from the software, especially inability to make sense of any exceptionally 'eco' construction.

garden office

jms452 — Sat, 01 Jun 2024 20:31:31 +0100

Hello all,

I'm working from home a lot and we need another office, so I'm planning to create a 2.2x2.5m office and inside part of a large detached wooden shed. The shed is decent and dry so I'm sort of creating a basic timber frame warm box.

My plan is to go low embodied carbon, cost effective and easy to assemble in couple of weekends.

Floor, 1000gauge dpm, 50mm phenolic [already salvaged from a skip], 18mm osb, second hand flooring tbd.

Walls/ceiling, old feather edge fencing planks to protect from damage, breather membrane, 100mm pavaflex, tapered edge plasterboard, filler + Paint.

Door (2 internal doors we already have one opening in, one opening out).

I was going to insulate it more, but given the tiny space I calculate even at dT=20 it will need <300W (i.e. a person, computer and monitor) so more insulation seemed pointless.

planning on fully breathable construction so no vapour control membranes

Am I missing any thing here?
I think we avoid regs as it's a shed?
(will run on an extension lead plugged into an outside weatherproof socket)

Is a single room heat recovery unit overkill?

thanks

edited for typo

Unable to Access using Chrome

Victorianeco — Wed, 29 May 2024 15:33:51 +0100

I cannot get onto the forum using Chrome only Firefox...

Anyone else having issues?

Hot water

djh — Fri, 22 Mar 2024 17:18:46 +0000

If anybody's interested, the government have published a new document "domestic hot-water use"

https://assets.publishing.service.gov.uk/media/65f43b919d99de001d03df8a/domestic-hot-water-use-insights.pdf

They seem to have collected a bunch of data from people who have "intelligent" boilers and maybe other things. Some interesting and some scary data.

Attaching PV using clamps

ComeOnPilgrim — Fri, 05 Apr 2024 15:34:27 +0100

Follow up question to my earlier one. I have a standing stream roof that uses S-5-E clamps. These have a vertical thread for an M10 bolt. Was wondering how to attach a rail for the panels to this and whether there needs to be a gap between the panels?

It's summer! :)

djh — Thu, 09 May 2024 19:32:29 +0100

Our MVHR opened its summer bypass late this afternoon. So I declare summer is officially here!

Huw’s Little bungalow renovation

Huwblut — Tue, 07 May 2024 10:52:01 +0100

Hello everyone, I’m new here and more or less a total novice so please be gentle with me!

I’m planning some work on my little detached bungalow. The areas I’m unsure about are insulation, ventilation and installation of windows.

I’ve attached a drawing done a while back which was part of an assessment for a heat pump. In summary I’m keeping the gas boiler as it’s a new 35kw Worcester. Hopefully the drawing will be useful.
I’ll keep it simple and just concentrate on the ceilings / floors for now

I’ve got a builder booked for 20th May.

The wall between the two “kitchens” will be removed making a kitchen diner.

The house looks like it’ll need a rewire and most of the ceilings are cracked so they’ll be coming down. There’s a couple of small rooms upstairs which don’t meet building regulations but have proven useful for the occasional visitor etc. The roof above that has been insulated with the exception of the small stud walls.

As it’s essentially a bungalow with an insulated attic. I’d like to insulate the ceiling / floor as I’m sure that I’m losing heat to the above rooms (even though they’re ultimately insulated from above). I guess it’s a similar proposition to insulating a suspended floor but from underneath.

Could anyone suggest a type of insulation to go between the joists please? I’d imagine foil backed foam sheets of some kind would be suitable (if not particularly green) but cost is definitely an issue so I’m open to suggestion.

Should there be a membrane of some kind fixed to the joists before the insulation is added?

Should I be paying close attention to any gaps or spaces not filled by the insulation around the edges or around the joists by using tape or similar?

Should I use a membrane over the isolation and under the plasterboard as vapour barrier?

I hope this makes sense!

I’m super grateful for any help.

Cheer

Huw

How long can cheap night rate electricity last?

Peter_in_Hungary — Sat, 11 May 2024 18:58:40 +0100

There happened to be an Ikarus bus exhibition in my local town with buses from all ages including the latest electric bus, a pre production model. It has a 280 kWh battery with a range quoted as 540 km. Fastest charging time quoted as 15% to 100% as 1 hour. - and they routinely charge to 100% as the normal procedure.

Talking to the Rep. the plan is to have electric buses replace the ICE buses over time with several town here already having electric buses. The charging routine would be to charge from 11 pm to 4 am. for 2 reasons 1) buses don't run at night and 2) the power co. like the night time load.

By the time there are fleets of electric buses, lorries, taxies and delivery vans from all the on-line sales not to mention private EVs where will the incentive be for cheap rate 'off peak' electricity.

BTW has anyone heard (other than pure speculation) what plans HM Treasury has to replace the lost revenue from road fuel tax.

Oh - and the drivers absolutely love the electric buses.

If I ordered one of the new buses today delivery is in 3 months. No one was talking about the Grid capacity except one driver who reckoned they would need a direct line to the nuclear power station.

So how long will the cheap night rate electricity last?

Crumbly lime plaster on wood fibre boards

bgasparotto — Tue, 02 Apr 2024 12:01:22 +0100

Hello folks!

I have been using Lime Green ready mixed products: Duro, Solo and Board Adhesive (lime based), which you only mix in the water. 2 out of the 3 walls went really well if I say so, but the third one is crumbly to a point that I can use a pencil to scratch the plaster off without breaking the tip!

The walls that worked:
internal bare brick < 10mm of Duro < another 10mm of Duro < 5mm of Solo
party wall existing lime render < 3 to 5mm of Solo

The issue:
external bare brick < 10mm of Duro < 5mm board adhesive < 60mm hard wood fibre < 8mm of Solo (two passes in the same day with mesh in the middle

The base coat of Duro was very strong as the others, and I was also happy with how the wood fibre bonded with the adhesive and mechanical fixings. However, a month after applying the top coat of Solo, it still feels crumbly (please see pics)

This is how I applied the plaster:

1. Added 5mm of Solo across the whole wall, pushing the sections of mesh as I plastered
2. Added 3mm of Solo on top of the mesh (around 4h after the coat above)
3. Sponge floated and used a smooth steel trowel for a smooth finish (about 2h after the second coat, it came out smoother than the other walls).

At the end of the same day I noticed some small bubbles coming out of the plaster, then also noticed it being a bit wet on the surface (like condensation), even though I left the window a touch open.

Would anybody be able to point what I did wrong? I followed the product guidelines to the best of my knowledge, especially when they say the first and second coats around the mesh should be applied within 24h, so I am a bit puzzled and scared to carry on plastering the other external walls the same way.

Any ideas are welcome and hope you are all having a wonderful week!

Air to Air Heating

kristeva — Tue, 30 Apr 2024 09:34:33 +0100

Hi all

I know this topic may well have been covered quite a bit on here before but I'm exploring the possibility of installing (DIY) an external air to air heating system for the ground floor of my small, old property (1800).

I just wanted to canvass opinions on the viability of such a project or perhaps get in touch (privately) with anyone with similar installs.

The space to be heated is open plan, approx. 419 sq feet / 39 sq metres. I could run ducting through the void in the floor. All external walls will be insulated with 60-80mm wood fibre board, windows are double gazed but old. I hope to have a wood burner in one of the chimneys too.

What kind of performance can I expect (South East of England) and what are the downsides? And is this something I could DIY myself (apart from the commissioning)?

One of the reasons this topic has become current for me is there is someone local selling 2 brand new unwanted cast iron radiators (2K each) which would be perfect for my house if I was going to use my boiler. They are selling at a fraction of the retail price, but i don't want to commit if I end up not using them as you can imagine shifting them on at 182KG will be a bit of a nightmare.

Many thanks.

Blum hinges

Rex — Sat, 20 Apr 2024 09:34:01 +0100

What ho one and all,

Following a leak (Drip Drip thread) from a SureStop mains stop-cock, I have found that a couple of the Ikea cupboard door hinges have rusted somewhat.

It is not a problem replacing with the same Ikea named hinge, although the design is different and I assume they would fit.

But my question is, would any other make of hinge fit Ikea doors? Basically, do all Blum hinges fit to the same temple?

Thanks and toodle pip

Building Insurance for SIP based construction

borpin — Tue, 30 Apr 2024 13:10:04 +0100

Has anyone else had issues with getting an insurance quote for a building incorporating SIPs?

I have an Oak Frame section of the house with Kingspan SIPs and on searching for a new Building's Insurance quote have come up against an unwillingness to quote as it is regarded as "an increased fire risk". Queried and went to a ''higher underwriter' but still the same answer.

Thoughts?

Any suggestions for a Broker to try (this was NFU).

Preloved StorEdge offered

yclairejenkins — Tue, 23 Apr 2024 22:09:01 +0100

This StorEdge interface was fitted in 2017 along with a SolarEdge inverter and original model Powerwall. We have now had it removed as the Powerwall has been replaced with a Powerwall 2 which doesn't need the interface.

I can send pics and try and find out the full model details if anyone is interested.

Also, if anyone can suggest where else might be a good place to find a buyer, that would be really helpful.

Approved details

fostertom — Mon, 22 Apr 2024 16:21:24 +0100

This is a dumb question, after all these years. We here think a lot about wall 'sandwich' build-up details, model them in WUFI etc, for interstitial condensation risk, air tightness etc. And lately, for example, I've found insulation suppliers such as Warmcel refusing to authorise their distributors to supply their product unless it's being done to a certified detail/design. Strangely, I can find nothing in Building Regs that makes similar requirement - which Part is about this, if not C (ground/rain) moisture, F vent/condensation, L thermal? No search term I can think of, produces refs to such details, tho I know manufacturers publish sample construction details, get BBA Certificates etc, on use of their product. So, question is, what different kinds of sources are there, for such detail/designs that can be used as evidence of approvability, if not certifiability?

Drip, drip, drip

Rex — Tue, 16 Apr 2024 17:50:28 +0100

What ho one and all,

When we built, I installed a SureStop to the incoming mains on the basis that if needed, my wife would be able to hit the button rather than try to figure out where the stopcock is located. And I do have a stopcock!

Yesterday, when putting some stuff away, I noticed the cupboard base was wet. further investigation revealed that the SureStop has a fracture in its body so a replacement is necessary.

Of course, nothing is simple as the replacement has a shorter dimension than the current model, which means I have to add about 20mm of copper. What a bugger!!!!

I have figured out how to remove the SureStop by undoing an elbow (out of shot) at one end which will hopefully, allow sufficient movement.

Lead Flashing Sealant - how important is the spec's width to depth ratio?

greenfinger — Thu, 18 Apr 2024 13:53:17 +0100

Hi

I'm finishing a lead flashing job and now need to seal the flashing that's turned into the chase. The lead has been fixed using hall clips. It's an old stone wall, with undressed stone. So nothing is straight or flat!

Although some seem to favour mortar, I've decided to use lead sealant. Some of the sealants specify that a width to depth ratio of 2:1 must be used (I guess at the end of the say this is a silicone, and the same ratio is also specified for other silicones such as sanitary types, etc).

Where this ratio cannot be achieved what might the implications be?

Having read/watch videos about the topic, it has got me to thinking. Lead flashing is commonly used against brick walls. The typical mortar joint is 10mm wide. The recommended chase depth of the lead is 25mm. So in this scenario, there would be a width to depth ratio of 1:2.5 and therefore well off the recommended 2:1 ratio. In fact, here's a couple of manufacturer's videos which seem to show the full depth of the chase being filled with sealant. The brickwork looks standard, so I presume the chase is no more than 10mm wide.

https://www.youtube.com/watch?v=PIVhKIbyxk4
especially at 1:29.

https://www.youtube.com/watch?v=GBtvHif6bTE
at 6:30

Similarly, I can't imagine every plumber using silicone adheres to the ratio.

So I wondered whether you guys think about this ratio business?

Cheers

A couple of Qs on continuous extract fans (dMEV)

luz13827 — Sat, 11 Sep 2021 16:30:17 +0100

Hello, unfortunately MVHR isn't suitable for our renovation for several reasons, so we're looking at monitoring + manual ventilation and fans in the kitchen/bathroom. I had a couple of Qs about the continuous extract fans

- I know that usually the problem is too much humidity, but could continuous extract fans, in theory, make the air TOO dry? How likely is this a problem in reality? We are planning to use clay board instead of plasterboard, which should help to buffer humidity already.
- What sort of heat loss is there with continuous extract fans?

Assuming we do still go with continuous extract, any recommendations for best model?

How to best insulate a piled foundations for a Passiv standard house

dovemw — Wed, 15 Mar 2023 12:52:09 +0000

I am new to the forum and have a new self build PH standard timber frame project in Surrey. We have planning permission and are about to get the PHPP modelling started. Our site is on sandy London clay and we are also about to get a full ground investigation undertaken to establish is we can do a strip or raft foundation or have to use a piled solution. The Geotechnical experts, a local structural engineer and two ground works contractors all think we will end up with a piled foundation and looking locally new build projects are using piles!

Does anyone have any advice on best way to insulate a piled slab supported by piles for a PH project? The default by the groundworks contractors looks like there will be anti heave measures then insulation under the slab and the slab itself. Is there a solution to avoid thermal bridging where the pile connects to the slab? I assume we could insulate above the slab and then use high compressive strength insulation under the timber frame sole plate to reduce the impact of the cold bridges, is this a good solution?

(I have been looking to see if there are any discussions on piled foundations on this forum and can't find any specific to this hence creating a new discussion.)

Wood Gasification (Log) Boiler Experience?

edwinvanek — Fri, 14 Sep 2007 12:33:56 +0100

Over the last 6 months we have been considering the replacement our old oil fired central heating boiler with a log boiler as both our tank and boiler need to be replaced over the next few years. We have compared alsmost every manyfacturer available (Dragon, Atmos, Vigas, Froeling, Hoval, Baxi, Mescoli, Viesman, ETA, Herz, Biotherm, Treco, etc) and haven''t been able to make a decicion yet. Recently we started thinking about keeping the oil fired central heating and adding two wood stoves, one connected to the warm water tank.
My preferde boiler would be the Austrian ETA boiler which I have seen in operationa t various locations in Germany, but the boiler itself without heat store and other component, flue and installation is close to 6K, which is too much. The middle way would be a Baxi Solo Inova. Does anybody have any experience with Vigas and Atmos boilers, which are the most economically priced boilers. The pros are: renewable ennergy, affordable fuel the cons are: costly, not as instantly controlable as oil and gas, bulky and expensive to install.

Before finally making my mind up I was wondering weather anybody who has already installe a log gasification boiler would be willing to share their experiences and or frustrations?

Edwin

Default mode

tony — Sun, 14 Apr 2024 09:03:28 +0100

A friend of mine has solved a problem that we might come across with other people. They have the Eco mode on their boiler, in other words they did not have preheating of the hot water. They were most surprised to hear my boiler come on, and upon investigation found that the Eco mode was off! They realised that this was because the electrician turned the power off when attending to a cooker switch. So what they learned was that whenever someone or something cut the power to the boiler, they will need to switch Eco mode on again when power is restored.

Why to boilers or at least that make default to not eco mode?

Airtightness retrofit

oliviaaa99 — Tue, 09 Apr 2024 10:52:47 +0100

Hi all! We are working on retrofitting a 1960s bungalow and are hoping to install a MVHR system. We’re getting a bit lost in how best to air tight the property with minimal disruption though.
Currently we’re looking at having a cold loft and the air-tight layer inside, the house has brick cavity walls and a substantial suspended timber floor cavity.

The walls and ceilings are currently being reskimmed, so I believe it’s too late to do much taping? We’re stuck on the floors as we ideally would like to insulate from underneath to avoid the mess of removing the floorboards, so are considering this structure (from top to bottom)
Engineered wood floor/carpet
Flooring underlay (?)
Plywood (sealed with tape)
VCL/vapour barrier/airtight layer
Floorboards
Insulation
Breathable windproof membrane

Essentially for now we would lay down a VCL then ply board over the top and airtight tape the gaps in the boards. Then at a later date once we've moved in, we would go underneath to insulate the floors.

We definitely aren’t aiming for 100% airtightness as I believe it’d be impossible in our circumstances, but hopefully to make enough of an improvement to improve the thermal efficiency of the house. I couldn’t find any information on the suspended timber airtightness that didn’t involve lifting the floorboards, so I was hoping to get some advice on whether our plan is doable or not (or if it’s just a recipe for trapped moisture!)

Thank you so much!

French drain

Artiglio — Fri, 05 Apr 2019 15:39:00 +0100

Iâ€™ve a wall in an 1800 house, semi basement 9â€ brick, at some point in the past the original wood floor was removed and filled with concrete and the walls â€œtankedâ€ externally the pointing has been redone in sand and cement. The wall is pretty much saturated and damp penetrates around the windows and points where the tanking has failed / was done poorly.
Pulling up the floor and redoing it, removing the tanking are neither economical or practical.
Its been suggested a french drain along the wall will at least prevent the wall getting any wetter and repointing with lime will help the wall dry out a little over time.

Plan is for a 600mm wide trench along the wall to 100mm below the concrete floor level, a studded dpm against the wall , a geotextile in the trench then backfilled , suggestion is to use cockle shells ( available locally) as this will give plenty of air space and quick drainage.

The wall will then be repointed in lime.

The homeowner understands that this will not make any immediate improvement , but that it should prevent further water being sucked into the wall and over time allow the wall to dry out a bit.

Is this a sensible way forward? Being a diy project its not overly expensive . Any suggestions to improve or new ideas?

TIA

Wholesale PV panel and kit source?

ComeOnPilgrim — Sat, 23 Mar 2024 22:44:39 +0000

I'm considering self installing a PV system while prices are low. Would anybody be able to recommend a potential wholesaler to source the parts from?

Want to see inside an 8 year old MVHR?

cjard — Fri, 09 Feb 2024 12:25:13 +0000

This yummy thing is the world side..

Kitchen cabinet door refresh

Rex — Wed, 03 Apr 2024 13:12:58 +0100

What ho one and all,

The Ikea kitchen cabinet doors and drawer fronts could do with a bit of a refresh. They are MDF factory painted white, some slight damage to a few bottom edges and generally slightly faded.

The options are new panels but to replace everything will be surprisingly expensive. Paint; could do that but will never look as good as the factory finish (and I don't have a compressor!)

Wondering about a self adhesive vinyl. Fablon does look a bit 'cheap' and will probably not fold around the slightly radiused edges.

So wondering if anyone has use the car wrapping film (https://www.mdpsupplies.co.uk/vehicle-wrapping)

This is an interesting video with no water used. https://www.youtube.com/watch?v=8Q3CS4rJRIk

Which does bring up a couple of questions. Given that it is a heat shrink, is it likely to 'fold/stretch' around corners to give an seam free finish? Secondly, I have applied similar film to some of our windows to reduce UV. One needs to spritz the glass first to avoid bubbling. Presumably, this would also be necessary to apply car wrap to either a car or in this case, MDF doors?

Grateful for any advice if you have 'refreshed' your doors.

Thanks and toodle pip

Lime plaster on plasterboard

bot de paille — Tue, 15 Dec 2015 17:47:55 +0000

So Im just offering this up as its the sort of thing people look for and I haven't seen it posted before...

If you want to put a skim lime plaster on to plasterboard this is a tried and tested solution. Also works on any wall surface that you want to skim as part of a renovation. I came up with it because Multifinish plaster doesnt exist in France and the local plaster is shite for skim finishing because it sets very quickly.

Prep the plasterboard or existing wall with 9 parts water and 1 part PVA glue which has sand mixed in. This will seal the wall and provide a mechanical fix. I wait until the PVA has set but still a bit tacky...

then plaster on the skim coat of lime/sand plaster. Mix 1 part NHL3 lime with 1 part sand and mix together using the same PVA/water mix used for the primer.
Use a fine, nice colored sand as it is this which will determine the final color of the plaster. Quartz sand can also be added.

And thats it. Finish the plaster as you want, either flat finish with a trowel or bring out the sand using a sponge when the plaster starts to set after a few hours.

If you live in one of those countries that uses gypsum plaster that sets within 20 mins, the missing ingredient you need to add to increase working time is trisodium citrate, a form of citric acid. You can also squeeze some lemon juice into the water as you mix the plaster. If you add too much the plaster wont set.

Exposed Oxfordshire Semi - Window Size Reduction

darthgarth — Fri, 08 Mar 2024 12:44:43 +0000

Hi All,

I live in a late '50s semi that has some pretty big (and pretty bad) alu framed DG windows. Sizes range between 25-40% of the external wall area of any of the rooms.

Due to the "outboard" positioning of the windows we get a lot of thermal bridging in the reveals - the brick outer leaf is within the heated envelope of the house and is a condensation horror show, particularly on the north side of the house. This is being mitigated in the short term with foil tape to stop the emulsion going mouldy in the perpetual winter damp which, as you imagine, is not terribly attractive.

I have been considering some approaches to resolve the thermal bridging when we come to change the windows but they would lead to a reduction in the dims of the window openings and a cascade of issues relating to lead times for new windows and the requirement to temporarily block the openings with somekind of ply/PIR/plasterboard sandwich for some time. Which would probably not be acceptable within the household - even I think it's probably too much to live in the dark for X number of weeks/months!

Is such an approach ever practical or would it just be better to take the money allocated for any remedial work and spend on better windows in the original openings with some other lightweight strategy to mitigate the thermal bridging (aerogel)?