Cost of retrofitting a house to A energy rating

Haille

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I have a large 4 bedroom dormer bungalow built in 1989. I was wondering how I go about improving the energy rating to A standard.The cavity walls have 2 inch insulation, Attic is insulated.I have double glazed teak windows with oil fired heating and open fireplace with back boiler.As the front of the house is sandstone external insulation on the front is not an option,Though the back and sides of the house could be insulated externally. I also have the option of dry lining internally also.Was considering installing heat pump and maybe solar panels.Just wondering is it possible to bring this house to A level given that there is no floor insulation.If anybody has done a similiar job any advice with regards to the above.Can one combine external insulation with dry lining. ?Trying to figure estimated cost with use of possible grants.
 
I have a large 4 bedroom dormer bungalow built in 1989. I was wondering how I go about improving the energy rating to A standard.The cavity walls have 2 inch insulation, Attic is insulated.I have double glazed teak windows with oil fired heating and open fireplace with back boiler.As the front of the house is sandstone external insulation on the front is not an option,Though the back and sides of the house could be insulated externally. I also have the option of dry lining internally also.Was considering installing heat pump and maybe solar panels.Just wondering is it possible to bring this house to A level given that there is no floor insulation.If anybody has done a similiar job any advice with regards to the above.Can one combine external insulation with dry lining. ?Trying to figure estimated cost with use of possible grants.

Do you want to have an A rated house on paper or make your house much more comfortable and easier to heat ... given that you mention using a heat pump, I'm assuming the latter.

There are a number of things that you can do to move your house up on the BER scale towards an "A" rating but not necessarily make much of a difference to how easy it is to heat the house and this is especially true for dormers. So be careful with where you choose to invest.

For example, dormers are notorious for excessive heat loss by convection (air leakage) and therefore no amount of extra insulation, whether external or internal, will address this significant heatloss mechanism, yet on paper it can improve the BER rating considerably.
 
Many thanks for that.While there are 2 big bedrooms upstairs.One of the bedrooms is not a conventional dormer room in that I have 4 block walls in one bedroom with very large window . The 2 nd bedroom is a conventional dormer with studded walls and side attic space which is a cold area.I have insulated this bedroom roof and the studded walls of the bedroom.It is the side storage space that is the problem.
 
EWI and IWI don't work well.
Why are the floors not insulated?
How do you know?
As noted earlier, bungalows are a ... to get right as a retro.
In round numbers, 80k, with maybe 1,800 savings based on the estimated improvement in U values and improved airtightness.

look at cases studies on the s homes site referenced earlier
Don't get fixated on grants, they don't benefit you.
 
Moving from a D to an A rating means getting energy consumption down by 75% to 85%.

That's a lot.

There are (I believe) limits to what you can achieve unless it's new build.
 
Many thanks.Back in the late 1980’s floors were not insulated .It was a self build.The standard cavity wall insulation at the time was 1 and a half inches. My architect recommended 2 inch which is what I used.If only he had recommended proper insulation back then.
 
Find your house type on this guide and review the detail on the options available with projected costs and payback period.

Note that while it may be possible to bring your existing house up to an A rating, it might cost so much you never recoup the expenditure in savings. A decent B might make a lot more financial sense in the long run.
 
Many thanks Leo for the above guide. A number of questions My house is an 1989 self build bungalow.There is a 2 inch insulation in the cavity wall.It was suggested in the guide to pump the remaining cavity with insulation and then add external insulation or dry lining on the inside.Which is best option? Is it best to get an overall survey of my house or should I contact companies directly myself.As regards dry lining would it be better to get a local carpenter to do this rather than getting somebody suggested by surveyor .Would it work out cheaper.As I am retired I have time to make contacts myself directly
 
As regards dry lining would it be better to get a local carpenter to do this rather than getting somebody suggested by surveyor
If the installer isn't very familiar with internal insulation and there's inadequate ventilation then dry lining can cause mold problems on the wall behind the dry lining, leading to poor air quality so I'd go with someone who installs internal insulation as their day job.
 
External is generally better, though more expensive. The main benefits are you don't lose interior space and (if installed correctly) there's less cold bridges leaking heat compared to internal insulation (though this may be less of a factor in a bungalow)
Just to add to above
EWI is far superior to IWI
- no loss in thermal mass (important for low grade heating systems such as heat pumps)
- zero risk of interstitial condensation / mould within the wall build-up
- specified properly, it can greatly reduce heatloss through uninsulated concrete ground floors
- no impact to internal wall finishes / fittings etc

Needs to be done properly though to get full benefit and also best in conjunction with a window upgrade.
 
Many thanks Leo for the above guide. A number of questions My house is an 1989 self build bungalow.There is a 2 inch insulation in the cavity wall.It was suggested in the guide to pump the remaining cavity with insulation and then add external insulation or dry lining on the inside.Which is best option? Is it best to get an overall survey of my house or should I contact companies directly myself.As regards dry lining would it be better to get a local carpenter to do this rather than getting somebody suggested by surveyor .Would it work out cheaper.As I am retired I have time to make contacts myself directly
Without a shadow of doubt, it is best to get the survey done first. You could easily spend 30+k on so called "improvements" and not reap the benefit, especially on a dormer. I've seen it happen a lot. Make sure your surveyor is independent.
 
As I am retired I have time to make contacts myself directly

Along with the above, there are various grants available including via the SEAI or your local authority (example).

The SEAI Deep Retrofit program looked great for significant jobs, but we're still waiting for the next iteration of that despite all the political talk of ambitious retrofit targets.
 
1. Is there a register of quality, independent surveyors @Micks'r?
2. What should I look for in a surveyor?
1. No, not that I'm aware of.
2. Qualifications (such as engineer, registered air tightness tester, passive house consultant for example). Experience in testing for air tightness, trained in use of thermal imaging equipment, in involvement in successful retrofit projects, in addressing the whole house as a system rather than discrete components, You are looking for somebody who can more or less guarantee that they can pinpoint & prioritise the weaknesses and where / how to invest in order to get the best bang for buck (not only financially but also comfort/wellbeing wise).
 
Note that while it may be possible to bring your existing house up to an A rating, it might cost so much you never recoup the expenditure in savings. A decent B might make a lot more financial sense in the long run.
While I agree with the jist of this in pure financial terms and it is a good point but it's not apples to apples, there is another angle which I think is important to mention. Not all the benefits of a deep retrofit can be measured in euros and cents. I'm talking here about the real but unmeasurable comfort dividend to be enjoyed by doing a proper job.
When a house has poor heat retention properties, it is generally "under-heated" by the occupants because it is perceived to be wasteful, i.e. the house on average is generally on the cool side of comfortable and also the outside weather conditions are readily noticeable inside. On the other-hand, after a proper deep retrofit job, the house is generally always comfortable for very little energy input and the outside weather conditions are not felt inside. This benefit is real but not easily measured in euros / cents as payback.
 
I'm talking here about the real but unmeasurable comfort dividend to be enjoyed by doing a proper job.

True, you can't put a value on smug, but it is important for people to understand that it is not always possible to achieve a payback, and the further you want to get towards an A1 on an old house, the more likely you are to be wasting money.

When a house has poor heat retention properties, it is generally "under-heated" by the occupants because it is perceived to be wasteful, i.e. the house on average is generally on the cool side of comfortable and also the outside weather conditions are readily noticeable inside.

I currently live in a G rated house, I don't suffer in the cold because of some notion that heating is wasteful. If the OP brings the house up to a B standard, there should be no problems whatsoever in maintaining a comfortable environment.

The key point is knowing what you really want to achieve and when to stop. To go from a B to an A rating, the OP may have to spend another €20-30k, they may not get much return from that in terms of comfort, and the payback period could be 40 years or more depending on occupancy.

I'd advise anyone considering a deep retrofit to try seek advice from someone independent and who isn't more interested in making a sale.
 
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