Insulating an old house

catswhiskerscats

Hi all,

We live in an old house - about 90 years old. It's brick with render outside. We have double glazing and oil central heating. Not much insulation in the loft. I want to insulate it more and know roughly what to do:

possibly cavity wall insulation, if not then indoor insulation panels on external walls, possibly double glazing (though hubby doesn't want to spend the money!) and loft insulation.

We do suffer from damp and mould inside in some rooms and I'm worried that too much insulation will make that worse. Does anyone have any knowledge about how insulation could affect this?

When it's cold we always get condensation on the windows in the morning (have window vac). I have a very efficient dehumidifier too.

Any advice or info would be gratefully received.

Julia

PS: Hello everyone, I've been reading the forums here for years but only finally registered to post. Hopefully I will be able to help people on here too.

Furts

Be very, very, very careful before going down the route of cavity wall insulation. In vast areas of Devon when building a new home full cavity wall insulation is forbidden. You may not live within these areas, but even so, you you are still deemed a severe risk area.

The fact that you have an existing home with a render face sets alarm bells ringing even louder. To then add that you currently have issues with damp and mould in some rooms makes the prospect a potential disaster.

I hope this friendly warning helps!

catswhiskerscats

I've not heard of cavity wall insulation being banned in parts of Devon - I've googled but couldn't find anything, do you have a link?

Yes I am aware that cavity insulation may cause more problems and that is why I'm asking - if people have experience of it. The house is very drafty at times and the one room that had secondary glazing smelt musty most of the time so we removed it. But I have heard of people in Victorian homes who've insulated and not had condensation problems.....I want to know what they did!!

Julia

saveallmymoney

Julia does your house actually have a cavity? I think it might be too old.

The absolute gold plated top thing to do if you plan to live their forever would be external wall insulation, double (triple?) glazing and loads of loft insulation.

Your cheaper alternative will to insulate the walls internally, but you will need to be careful about condensation - vapour barriers, thermal bridges around windows etc...

Furts

catswhiskerscats wrote: »

I've not heard of cavity wall insulation being banned in parts of Devon - I've googled but couldn't find anything, do you have a link?


Julia

I do not have a link, largely because the advice is a subscription service. It is a fact that NHBC have banned full fill cavity wall insulation in much of Devon for various types of cavity wall for as long as I can remember. This is an item covered in their Technical Standards Chapter 6.1. I have not popped the latest CD into the computer but I doubt matters have altered since the hard copy I have to hand dated 2011.

Local Authority Building Control Warranty is likely to have a similar clause. Without doubt, were I in your position I would be speaking with my Local Authority Building Control about this.

Much of Devon is deemed "Very Severe" for "Exposure to Wind Driven Rain". I appreciate that you are not building a new home but the guidance is issued for a reason!

catswhiskerscats

Ok thank you both. We do plan to stay but we are a semi so external insulation wouldn't be possible - I'm assuming that it adds size to the house.

Thanks

DRP

Having lived in several similar age properties, IMO If you're trying to make the place warmer, then more/bigger radiators and sorting out drafts will be your most cost effective solution.

edit: obvs loft insulation very important.

edit: You say you have double glazing - is it actually any good? draughty, blown dg panels, old?

jonesjw

Everyone gets condensation on single glazed windows. Don't worry about that.
If you're worried about external damp ingress, there are water repellant coatings available. Screwfix sell one which seems effective.

Insulating the loft is a no brainer. Just note that the experts recommend a moisture proof membrane should go under the insulation.

Furts

jonesjw wrote: »

Everyone gets condensation on single glazed windows. Don't worry about that.
If you're worried about external damp ingress, there are water repellant coatings available. Screwfix sell one which seems effective.
.

But only treat the areas you feel definitely require this and do not go overboard with the application. Do not take the viewpoint that "it might help if we also do that area". There is a risk that you may increase damp and condensation if you adopt such an approach.

tea-bag

I am buying a house with solid walls. I am going down the loft insulation. Double glazing and new boiler route. I am also adding one of these,
http://www.fixmyroof.co.uk/videos-and-guides/condensation-cure/piv-unit-system/