Neighbour installing cavity wall insulation. Any advice?

h.cowell

Hi,

My semi-detached neighbour has just told me that he is having his cavity walls insulated in a few days time. Our house was built in the 1920s and suffers quite badly from condensation, particularly in the winter. As far as I know, our side of the property has not been insulated in this way, but both sides do have rendering.

Is there anything I should be aware of? Or is are we likely to be unaffected by this? I would like my mind put at rest if possible, since I saw a recent report by Dom on the One Show talking about potential problems, especially if walls were exposed to driving rain (the fronts of our houses often flood to a few inches because of poor drainage during heavy downpours - and our area is one of the wettest in the Country).

Suzy_M

Obviously its' only the external walls but it depends how the houses were built together whether there will be any leakage in to your walls and whether this may cause you any problems.

More in-depth info on problems here:
http://www.bbc.co.uk/wales/x-ray/sites/allarticles/updates/10p23_insulation.shtml


Are they really cavity walls - 1920s built houses with rendered walls suggests to me they may be solid wall construction -

http://www.energysavingtrust.org.uk/Home-improvements-and-products/Home-insulation-glazing/Cavity-wall-insulation/How-do-I-identify-whether-I-have-cavity-walls

fluffymuffy

h.cowell wrote: »

Neighbour installing cavity wall insulation. Any advice?.

Yes. Get yours done too.

27col

h.cowell wrote: »

Hi,

My semi-detached neighbour has just told me that he is having his cavity walls insulated in a few days time. Our house was built in the 1920s and suffers quite badly from condensation, particularly in the winter. As far as I know, our side of the property has not been insulated in this way, but both sides do have rendering.

Is there anything I should be aware of? Or is are we likely to be unaffected by this? I would like my mind put at rest if possible, since I saw a recent report by Dom on the One Show talking about potential problems, especially if walls were exposed to driving rain (the fronts of our houses often flood to a few inches because of poor drainage during heavy downpours - and our area is one of the wettest in the Country).

To coin a phrase. Get yours done as well. If the outside is rendered then there is little chance of driving rain being a problem.

swagman

Yes, get yours done but check first whether you are eligible for any grant towards the cost e.g. some energy companies, some local authorities will cover part of the cost.

We noticed savings in fuel costs after having cavity insulation done.

jonesjw

Never mind the damp -won't be a problem. Think of the warmth & money saving.

uncle_buck_3

If you do have cavity walls & you decide that you don't want insulation make sure that the company doing the job next door use a "cavity barrier"...this is to stop the insulation blowing into your walls as well as next doors.

Take a look at the link below for:

"MY HOUSE IS SEMI-DETACHED. HOW DO THEY STOP THE INSULATION GOING IN TO NEXT DOOR'S CAVITY"

http://www.tamesideinsulation.co.uk/index.php?option=com_content&task=view&id=28&Itemid=29


Cheers.

David_Aldred

The British Standard BS8208 which discusses suitability of properties for cavity wall insulation was withdrawn in the middle of last year but contains some very good recommendations one of which is any property with a problem of dampness of which condensation is the most common form should not be considered for cavity wall insulation. Please look at my other posts on this forum regarding cavity wall insulation which may be of some help to you but if your house is not to be cavity wall insulated then yes some type of dam appropriate for the property, the cavity and the insulation material should be installed. Despite some of the comments above cavity wall insulation is not appropriate for all properties despite it being installed to the majority without significant problems. Please advise your neighbour to consider having the cavity wall ties addressed prior to cavity wall insulation installed due to the reasons mentioned within my other posts on this forum regarding this subject. Hope this helps ,kindest regards, David Aldred Independent damp and timber surveyor.

evilgoose

I'm of mixed opinion regarding retro fitted cavity wall insulation - ok, your house will be warmer BUT the cavity is there for a reason, I'd rather put a jumper on than have a damp problem in the house. With a new house, the cavity is wider, to allow for the cavity and for the insulation.

my mum's house is stonebuilt with no cavity, but the kitchen, which is an extension, does. It was insulated last year, it's not made it much warmer and has made the condensation problem in the kitchen worse.

My house (which I'm renovating) is a semi, with a cavity. Next door has had insulation done (which they've had the firm back to redo as they have had damp problems with it).
I've spent alot of time knocking bricks out of the wall to gain access to the cavity to clear it of debris, of which there was an awful lot! I could see the isulation from next door where is had come into my cavity - no barrier has been fitted. It had also blocked up some of my airbricks and the company had also sealed the 'shared' airbricks.
Just a couple things to watch out for.

macman

evilgoose wrote: »

I'm of mixed opinion regarding retro fitted cavity wall insulation - ok, your house will be warmer BUT the cavity is there for a reason, I'd rather put a jumper on than have a damp problem in the house. With a new house, the cavity is wider, to allow for the cavity and for the insulation.

my mum's house is stonebuilt with no cavity, but the kitchen, which is an extension, does. It was insulated last year, it's not made it much warmer and has made the condensation problem in the kitchen worse.

My house (which I'm renovating) is a semi, with a cavity. Next door has had insulation done (which they've had the firm back to redo as they have had damp problems with it).
I've spent alot of time knocking bricks out of the wall to gain access to the cavity to clear it of debris, of which there was an awful lot! I could see the isulation from next door where is had come into my cavity - no barrier has been fitted. It had also blocked up some of my airbricks and the company had also sealed the 'shared' airbricks.
Just a couple things to watch out for.

That is an indication that the kitchen is warmer, as it's holding more water in the warmer air. Which would indicate that the CWI is having an effect.
When that air hits the colder window areas, condensation results. The solution is to improve the ventilation.

evilgoose

The kitchen certainly isn't warm!
We get condenstion running down the walls and windows and the door. And we've put in an airvent, the downside then been you get a draft.