I'm plan to use this thread to talk about a (very) small workmans cottage built in about 1850 which has just had a Green Deal assessment, and what happens to the bills as various things have been done to it.

This is anecdotal rather than a Steamy Tea computo-megamodel, but I hope it will be of a little interest.

First, the basics.

The place is 2 up 2 down, with outside dimensions 21' x 12'6", making up lounge 12x11, bedroom 12x11, kitchen 11x8, bathroom and boxroom. Construction is solid 9" walls front and back, half brick one end, half brick with an extra brick skin the other end. No foundations of course, and quite cheaply built.

Windows are currently custom-made hardwood small pane single-glazed from about 1982, when there was a major refurb. That will probably get double glazed before long.

All rooms have 3 outside walls :-). The site is windy.

Various things have been done over several decades, which I will come back to, and I am aiming for bills to get cut by about 60% from what they were 2-3 years ago, which may be worth well over £1000 a year in savings.

Ferdinand

I'm being slightly unclear about the "process", because I'm not sure *exactly* what it is :-).

This is not exactly "Green Deal" as such; it is ECO Affordable Warmth, which gives me a Green Deal type assessment and the possibility of funding, as this is a tenanted property (though I used to live there years ago) with T eligible for funding.

Being a tenanted property adds a different perspective, since any investment I make is competitive with a - my income and b - investment in other properties. I'll post about that too, since I haven't seen much of that on GBF and a lot of properties are now rented. In practice there are many extra factors involved.

The electronic model built by the Green Deal surveyor came up with an estimated current elec and gas cost of £80 per month, which is just under half of the actual current figure, which is already down by 25-30% over several years (new upvc doors, better appliances, loft insulation, drylining).

I can account for about half of that difference due to the way the property is used and power going to things which are not covered in the assessment.

But that still leaves me questioning the accuracy of this model for properties such as this one. It's a hell of an error tolerance.

The difference is actually less than it should be, since the assessor missed or ignored quite a lot of well-integrated dry lining which exists in the house, which would have reduced the estimate even more.

Ferdinand

Eh, that's not "very small",thats just as big as my house!

I'm interested as it's quite close and size and construction, with the main (big!) difference being that mine is a mid-terrace. :-)

I do wonder about the energy usage though. I can't give you whole-year figures as I've only been here for a few months, but at the moment my whole-year projection is under 600 kWh electricity and under 9000 kWh gas (projected using winter figures!).
All I have is standard (free) loft insulation, and DG.

Is that mainly usage differences, or just a convincing argument for terraced buildings?

Posted By: squirrelEh, that's not "very small",thats just as big as my house!

I'm interested as it's quite close and size and construction, with the main (big!) difference being that mine is a mid-terrace. :-)

I do wonder about the energy usage though. I can't give you whole-year figures as I've only been here for a few months, but at the moment my whole-year projection is under 600 kWh electricity and under 9000 kWh gas (projected using winter figures!).
All I have is standard (free) loft insulation, and DG.

Is that mainly usage differences, or just a convincing argument for terraced buildings?

I thought terraced housing normally had a bit (typically the kitchen downstairs and bathroom upstairs) that sticks out at the back, thereby negating any surface area to volume ratio advantage?

Maybe it's a regional thing, but my parents' house and pretty much every other one I see round here is like that. In fact as it's end-of-terrace it has a lot more external wall than my perfectly square semi!

Ed

Heh. Thanks all. Build date was a little before 1850. The bricks are of noticeably low quality - crumbly but with occasional nodules that kill masonry drills.

The official EPC Floor Area is 46 sqm, and the energy figures sound horrific, but that is already down quite significantly from 3 or 4 years ago. The washing machine change has been very significant in savings.

I think that a reduction by 30-35% from the figures above may be reasonable without EWI, and maybe 50%+ if I am able to do EWI.

The total wall area to eaves level is around 100sqm.

Ferdinand

Yes my house has a bit 'sticking out'. In some terraces this are original 'annexes', but here its just a collection of extensions, with the yards nearly completely build over. They do increase the outside wall area, but usually not as much as a semi could, especially as most of them are build directly onto the neighbours' extensions.

Obviously, if you had well designed new terraces, you could minimise the outside wall area even more. Most people have extensions because the houses had no indoor toilets originally.

Re the difference it makes - depends how much your neighbours heat. ;-)

I have had two terraces with 'sticky out bits' and two without. 2 end of terrace and 1 semi. This is the only one I have taken an interest in though (energy wise).
My 1959 build end of terrace in Aylesbury cost next to nothing to run and was almost twice the size of this place (no sticky out bit but had a garage to one side).
This one has a lot of window area though. I keep meaning to CAD it up and 'spreadsheet' it properly sometime.

EWI questions to ask.

I have a "Technical Surveyor" chap coming in a few days to assess whether this small house receives none, some or full funding for EWI.

Can anybody advise on questions to ask? Is there a thread I can't find?

The approach they use is to EWI down to DPC level (roughly), and I don't think I can persuade them to vary that, given that I couldn't even get an EPC discussed over the phone despite trying quite hard. If I want to have a skirt I will have to make my own afterwards.

I already have:

Thickness?
Type of insulation?
Which items of spec. can be varied. In what way?
What are any risks attached to the exposed location?
Finish of exposed edge at bottom of the EWI.
Window details (should any replacement windows be fitted before or afterwards?)
Is it dog-proof :-)?
What about airbricks? (I have some insulated drylining ventilated from outside due to a previous damp issue).
Eaves and gable detail?

Thanks

Ferdinand

It is now a few days since the ECO-funded boiler was fitted.

It is a Viessmann Vitodens 100W (I think: 30kw), which I mentioned on another thread. It seems to be a relatively basic boiler (controls: tap water temp and heating water temp), but with a 10 year guarantee and not to be an el cheapo bit of tin - which is a compliment to the ECO programme.

Had a play with the controller -(relatively basic) and it seems to have a M-F programme and a Sat/Sun programme, with easy manual override.

Interestingly it seems - I am told - to have weather compensating gubbins inside ready to connect to a sensor.

F

Just to add costs to this thread.

All the above has now been done, including Grade A double glazing and new upvc doors, but not EWI.

I have also added a large 24sqm well insulated conservatory/garden room which has doubled the size of the ground floor and enveloped a significant area of poorly insulated wall.

And the central heating system has been replaced with a new boiler/rads, which makes it better but the old one was efficient but wearing out.

The annual energy bills for both gas and electric combined are now £1400 rather than the £2700 it was before we started 3 years ago. As prices have increased by some amount, the energy saving will be more.

So cost per sqm is down by perhaps 60%.

Ferdinand

I am talking to the Council about EWI now that I have done the windows, but nothing has happened about the skirt yet except that just under 30% of the periphery of the house itself is now up against a large well insulated garden room with insulated walls and floor which must make a difference.

They are insisting that we have another Green Deal Assessment next week, since things may have changed after doing that the stuff they recommended last time :-) from the GDA 16 months ago.

In theory there is I think 66% funding available up to 6k and another 1k on top from ECO(?) Funding given that the occupants qualify.

Ferdinand