robert 200
Registered User
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I found this winter particularly cold in my home . Any ideas how one could improve the B.E.R. without too much fuss.
Thank you
Thank you
Improving B.E.R. rating
- Thread starter robert 200
- Start date
Firstly BER and cold are not the same thing.
First port of call would be get a BER assessment. They'll tell you what to do.
I'd be checking the attic insulation. Without it your house is a chimney. It's probably the cheapest improvement you can make and possibly the most noticeable in terms of retaining heat -depending on the level of insulation you already have.
First port of call would be get a BER assessment. They'll tell you what to do.
I'd be checking the attic insulation. Without it your house is a chimney. It's probably the cheapest improvement you can make and possibly the most noticeable in terms of retaining heat -depending on the level of insulation you already have.
Hooverfish
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I've been looking into updating insulation for an old house. In my researches, heat losses from buildings are typically:
Roof 30%
Chimney 20%
Walls 25%
Windows 13%
Ground 7%
Thermal bridges 5%
So start with roof. I also found this document, which I think moderator Leo originally posted, excellent as it classifies types of house found in Ireland and which measures have best effect on BER for those types:
We had a BER done alongside a "community energy audit". It really was utterly useless - it overestimated our actual energy use by 100% as they use a dreadful spreadsheet promulgated by the SEAI. It then advised us to do lots of things we cannot because of the type of building. So instead I would start by doing all the obvious things indicated in the PDF linked.
Then depending on the type of house, try and get someone who has some installation experience, not just a spreadsheet-plugger, to come and look and advise. I know draught leakage tests are also advised but in many old houses this is pointless as they actually need draughts for ventilation. But if your house is recent, one of those tests may help you pinpoint the best actions?
Good luck!
Roof 30%
Chimney 20%
Walls 25%
Windows 13%
Ground 7%
Thermal bridges 5%
So start with roof. I also found this document, which I think moderator Leo originally posted, excellent as it classifies types of house found in Ireland and which measures have best effect on BER for those types:
We had a BER done alongside a "community energy audit". It really was utterly useless - it overestimated our actual energy use by 100% as they use a dreadful spreadsheet promulgated by the SEAI. It then advised us to do lots of things we cannot because of the type of building. So instead I would start by doing all the obvious things indicated in the PDF linked.
Then depending on the type of house, try and get someone who has some installation experience, not just a spreadsheet-plugger, to come and look and advise. I know draught leakage tests are also advised but in many old houses this is pointless as they actually need draughts for ventilation. But if your house is recent, one of those tests may help you pinpoint the best actions?
Good luck!
lukegriffen
Registered User
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Attic is first step, everything else probably involves large money. I got triple glaze windows at start of April & haven't turned on the heating since. If you're thinking of doing improvement work sometime in the future, don't wait years like I did, you just end up paying higher bills during those years. The libraries have an energy saving kit you can borrow, - it has a heat reading gun which can help identify cold spots , but it would need to be a cold day.
You can improve the B.E.R. without too much fuss by changing your lightbulbs to energy saving ones but this will not make your house any warmer, in fact, the opposite
With respect, no one here can tell you how to make any meaningful difference to your house because no one here knows your house. Yes, you will hear different anecdotes about what worked for some people and what didn't. How applicable these are to your house nobody knows.
Having your house B.E.R. assessed and getting a cert & report probably won't be of any use either because it is not designed for that purpose, believe it or not.
If you are serious about addressing the real cause of the cold you felt in your house then it's best to take a holistic approach. I suggest you investigate having a detailed heat loss survey carried out on the house with an independent company (independent in the sense that they do not sell any other product or service). This survey is NOT a B.E.R. and will pinpoint the top priorities to address.
Hooverfish
Registered User
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It would be really interesting, as I know you have expertise in this area, if you spelled out what elements you think should be included in a general heat loss survey? I saw recently on one of the facebook house renovation sites a suggestion that larger public libraries now have heat loss cameras to lend out - this surprised me! Haven't investigated further myself yet on that one, but it interested me more than the air pressure tests. How much (roughly) does a heat loss survey cost?
In the last year I paid an energy expert to come and do a survey of the whole house so that I’d have a list of things to do over time.
The end result was that it highlighted that we’d done all the easy stuff, insulate the attic, better windows, energy efficient boiler. It also outlined the options for insulation on the walls, internal/external etc and a guide price for the works that allowed we to see the cost benefit over time (external insulation would take nearly 35 years to pay for itself). It was a worthwhile exercise
The end result was that it highlighted that we’d done all the easy stuff, insulate the attic, better windows, energy efficient boiler. It also outlined the options for insulation on the walls, internal/external etc and a guide price for the works that allowed we to see the cost benefit over time (external insulation would take nearly 35 years to pay for itself). It was a worthwhile exercise
Briefly ...
Why do we need heating systems in houses? ... Is it to heat the house or replace the heat lost from the house... Hint, it is the latter.
So how is heat lost (or transfered to the outside)? ... Conduction, Convection & Radiation ... ALL 3 modes are relevant in housing, some more-so than others in Ireland ... insulation generally only addresses one of these ... the other two are just as if not more important in the Irish climate context ... In addition, appropriate ventilation is a vital part of any solution so a holistic approach and applying building physics principles always yields the best results. Testing, finding, ranking, explaining the relevance of each finding & offering solutions is, in my experience the essence of a heat loss survey. Obviously, all findings etc are written up in a detailed report & sent to the client.
I wasn't aware of the libraries offering. Thermal imaging equipment, while extremely useful to the trained professional, is really just another tool in the toolbox and like any tool it is of little real value (possibly leading to costly incorrect interpretations) in the untrained and inexperienced hand.
Expect to pay in the region of €600 for everything ... to give an actual recent example of how cost effective this can be ... had a client recently who reckoned he would need to spend in the region of €10 to €15k to make a decent impact on the heat loss in his small 2 bed home. As normal, he had some preconceived ideas of where the problems were and what needed doing and was skeptical about having the survey done & what "value" it would add. He followed the advice from the survey; his total outlay was approx €3,600 and he can't believe the difference in the place both in comfort & indoor air quality terms not to mention reduced heating bills (order of 60% but with a comfort dividend). And this outlay included the survey fee!
Was air tightness not covered (tested for) in the survey?
Nope, no airtight testing.
Well then one of the major reasons why most houses are poor at retaining heat was overlooked
Hooverfish
Registered User
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Micks'r - you post interesting information often regarding BER, houses, heat surveys and you almost always recommend air tightness surveys. You've been very straightforward about the cost of your surveys at around €600. I agree draughts in our climate are the biggest problem! These air tightness surveys are great for recently built houses.Well then one of the major reasons why most houses are poor at retaining heat was overlooked
But I have yet to see you tackle the thorny issue of the one third of houses in this country that were built before 1980. We also have about 10% of our houses that are stone-built or single skin brick mostly pre-1945. The vast majority of those cannot be "sealed" as they need ventilation or they will become damp, unless you are talking about very expensive mechanical ventilation with heat recovery.
Can you explain what you recommend (other than you have the air tightness kit...) and what methodology you use for these older houses? I am definitely not against paying you (I'm in Cork which is not too far), but after being burned for the cost of the useless and impractical BER survey promoted by SEAI under its community subsidy scheme, I want to be sure something useful will result, that we can actually cost and take action on!
If you have tackled this in a previous thread, I just haven't found it, do post a link... Thanks!
Hi Hooverfish, some great questions.
You are correct in that the newer generation of housing (imo, since the proliferation of 8x4 sheets of plasterboard as a lining system to external walls) suffer greater from air tightness than the older vintage. And because the older housing stock are generally more airtight they can easily suffer from damp due to inappropriate or under ventilation especially when some "improvements" are indiscriminately retrofitted without heed being paid to their breathability requirements such as better sealed windows, replacing an open fire with a stove or internal unbreathable insulation systems.
I'm not sure where you get the idea that older housing cannot be "sealed". Building physics does not discriminate between build types or eras. All buildings of whatever vintage need appropriate heating (to replace lost heat) and ventilation (to exhaust moisture). How you deal with each very much depends on the building in question, its layout, use, etc. In the context of older buildings, such as lime based mortar stone walls, I have a feeling that you may be conflating air tightness / ventilation with building fabric breathability. To be specific, there is nothing stopping you from addressing air tightness weaknesses in a stone walled era building once appropriate ventilation is part of the solution as well as not restricting the natural seasonal movement of moisture through the breathable structure (i.e. do not seal in or trap the moisture in the structure).
There are also other forms of appropriate mechanical ventilation systems other than the mvhr type so it is not prohibitively expensive to achieve a decent improvement once the real building physics weaknesses are found / understood / addressed.
So, to sum up, my methodology is very simple ... accept there will be moisture movement in / out of the building and make sure that any excess moisture is exhausted as quickly and as efficiently as possible ...
Was a company on the Pat Kenny show this morning that provide you with a survey, it includes everything you need to get high BER ratings. Forget the Co's name but just look up the show this morning and it's there. He came across very well indeed. Worth having a look, instead of guess work, etc.
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Should this not read "less airtight"?
Glad I didn't block the fireplace with a stove. I thought about it but I think it was something you said in a post a couple of years back that helped me make what I now believe to be the right decision. I'm in a 1980's house and I've definitely improved heat loss by doing some DIY jobs such as:
- Adding 200mm of insulation onto the original single layer of attic insulation plus lagging the water tank and insulating the attic hatch
- Filling the gap between skirting and floorboards (I used strips of cork).
- Improving the seal around the hole-in-the-wall vents in the bedrooms and kitchen with expanding foam to prevent cold air getting into the wall cavity - although I suspect this might have been a pointless exercise because there are probably other ways that cold air can get through the outer brick wall and into the cavity.
- Replaced single glazed windows with double glazed.
No! In general, older structures tend to be more airtight due to the materials and construction methods original used (unsealed suspended floors excepted). In addition and given the context of the op, older properties also tend to be easier (more straightforward) to make meaningful improvements to the air tightness for the same reasons.