House with solid brick walls and external insulation

RHemmings

I hope this is the right place to ask this question. I'm viewing a house on Monday that has solid walls. According to the EPC (C, potential for , it has external wall insulation. I can't see that in the photos - the house and its partner semi-detached house are white while other houses in the street are plain brick, but I can't see enough detail in the photo to be sure. 

I'm asking now so that hopefully I'll be better informed by the time I view the property. 

How can I recognise the insulation when seeing it, and know how thick it is? (Clearly I will ask too, but would like to be able to see.) Will it be obvious from close up? 

Will buying a solid wall house seriously limit how energy efficient I can make it? I read online that 100mm of external insulation will be more effective than a cavity wall house with cavity wall insulation. But, surely if you have cavity wall insulation that doesn't stop you adding external insulation as well. 

Any other pointers or advice would be greatly appreciated. Both things I can inspect/ask about during the viewing and information/advice in general. 

Swipe

All the info should be in the EPC report. Look it up online.

sammyjammy

A house on our street has external insulation, it will look like its been rendered, the bricks are underneath the insulation, when you visit you'll be able to see it around the bottom of the house.

RHemmings

Swipe said:

All the info should be in the EPC report. Look it up online.

I've read the EPC report. It doesn't give the thickness of the insulation, just that there is external insulation. It also doesn't answer my other more general questions. 

sammyjammy said:

A house on our street has external insulation, it will look like its been rendered, the bricks are underneath the insulation, when you visit you'll be able to see it around the bottom of the house.

Thanks. Is it typically visible enough so that the thickness can be seen?

I've seen houses with external insulation before and it was very obvious even from a photo. On the house I'm viewing, they seem to have done a much better job on making it look ... 'natural'. 

[Deleted User]

As as part of any pre-purchase disclosure, the seller should be asked to provide details of what was done; when it was done and what, if any, warranties apply to the external insulation.

FreeBear

sammyjammy said: A house on our street has external insulation, it will look like its been rendered, the bricks are underneath the insulation, when you visit you'll be able to see it around the bottom of the house.

A couple of the houses in my neighbourhood have external wall insulation that was done under the Green Deal scheme - The finishing detail around bay windows, roof line, and downpipes (from the bathroom & guttering) all look horrible. Ignoring the ugly bits, the smooth rendered finish is an improvement over the old rough cast render.

With solid brick walls, you need to be very careful about the type of materials used - Go slapping on EPS/PIR boards and coating it with K-Rend runs the risk of trapping moisture in the walls. If meticulous attention is not paid to the detailing around the roof line, water will get in behind the insulation. Over time, this water will cause no end of problems internally.

In my opinion, it is much better to fix insulation to the walls internally - For a solid brick wall, ~100mm of woodfibre or cork finished with a lime plaster will make a huge improvement whilst still maintaining the breathability of the walls. You also have opportunity to continue the insulation round the window/door reveals and kill any cold spots in those areas. Downside to insulating internally is a slight loss of floor space and extra complexity when hanging radiators, curtain rails, and wall cabinets.

sammyjammy

RHemmings said:

Swipe said:

All the info should be in the EPC report. Look it up online.

I've read the EPC report. It doesn't give the thickness of the insulation, just that there is external insulation. It also doesn't answer my other more general questions. 

sammyjammy said:

A house on our street has external insulation, it will look like its been rendered, the bricks are underneath the insulation, when you visit you'll be able to see it around the bottom of the house.

Thanks. Is it typically visible enough so that the thickness can be seen?

I've seen houses with external insulation before and it was very obvious even from a photo. On the house I'm viewing, they seem to have done a much better job on making it look ... 'natural'. 

Yes its pretty visible if you know its there but  I guess that doesn't tell you the thickness of the insulation as it could be structured in a way that its hollow in the middle.  Presumably they will be able to provide you with some info about the type of it so you can do some research.   

RHemmings

Thank you so much everyone for the information. I hope there's nothing wrong with the insulation on this house as it's ticking a lot of boxes otherwise. But, I need to tread carefully and not rush in. You've all given me a lot of questions to ask on Monday, and I'm hoping the answers will be good. 

If there is a not-very-good seal on the external insulation, then is this something that can be fixed, or is it something that once done not properly, will forever be a problem unless the insulation is ripped off and replaced? 

I'm not familiar with internal insulation, and will do some reading. 

Thanks again everyone. 

Netexporter

External insulation is generally preferable to internal insulation because it doesn't reduce your useful floorspace and it places the dew-point outside the building envelope, so there is less risk of interstitial condensation occurring. However, detailing around openings is tricky and needs to be done with great attention.

There are many systems of external insulation but typically it will consist of foam insulation blocks bonded and mechanically fixed directly to the brickwork and then rendered over. I recently saw a good YouTube video by a geezer going under the name of Skill Builder that goes into the ins and outs of that type of system.

RHemmings

Thanks @Netexporter, I think I found the video you meant. 

https://youtu.be/z53EWwDYNao

I note the concerns about moisture. I was planning to install some sort of heat exchange ventilation system in any house I purchase. I note the issue with moisture and black mold, and will look for it. But, the house looks fine in the photos. While it could be covered up, I certainly see a lot of photos of houses for sale around here with no attempt to hide damp and mould and who knows what. 

I'm currently sitting in a very large master bedroom in a rented house. Even if this house has cavity wall insulation ... checks EPC ...  nope, solid brick walls with no insulation, it would be easy to put in a 10cm internal insulation layer and still have plenty of room space. The bathroom would be tricky - need to move the bath. And the hallway and stairs - I don't see how that could be done. 

[Deleted User]

RHemmings said:

Thank you so much everyone for the information. I hope there's nothing wrong with the insulation on this house as it's ticking a lot of boxes otherwise. But, I need to tread carefully and not rush in. You've all given me a lot of questions to ask on Monday, and I'm hoping the answers will be good. 

If there is a not-very-good seal on the external insulation, then is this something that can be fixed, or is it something that once done not properly, will forever be a problem unless the insulation is ripped off and replaced? 

I'm not familiar with internal insulation, and will do some reading. 

Thanks again everyone. 

If you are concerned then pay for a structural survey. The surveyor will be able to address any concerns that you have and if the advice is proved to be incorrect, you can always sue.