Questions regarding insulation and old Victorian homes

[Hugh Jaleak]

My personal opinion, hold fire until the installers can show you some credible back up to support their claims. I'm with Dishman, I've not heard any good reports about that stuff, I cant see how they'll get it into the cavity (if there is one!), and once it's on/in you wont be getting it off/out again.

If it does cause serious problems then you're up the proverbial creek without a paddle, and until you're totally satisfied it wont do more harm than good I'd steer well clear!

There are ways to insulate walls, and that to me is not one of them.....

 

[boilernoob]

I agree Hugh mate. He's taken me to a house where this has been done and I can clearly see it.

FYi, he's explained how it's done...

...Small Holes are drilled into the external walls and it is then pumped/sprayed in with pressue whilst it is hot and runny, allowing it to get to those hard to reach gaps. Once the cavity/gap has filled, it dries to become exactly like expanding foam would be.

 

[Hugh Jaleak]

A similar method I believe to that used some years ago. There was a company local to me who were installers of a foam type cavity wall insulation in the late 70's/early 80's. I heard several stories about householders having had this foam pumped into the cavity in their homes, only then to find members of the family were suffering allergic reactions, which were apparently attributed to this product. By this time they'd a serious problem. The foam was in, and there was no way of getting it out.....

The company (obviously) denied any links, but didn't remain in business for much longer afterwards. There are a number of stories that have gone about over the years about the ethics of the management of that company, (and other dealings they've had since), which on the whole would make the story about the problems with the product wholly believable. Just bear in mind, once this stuff in in, it's not coming out again. You'll have to demolish the house before getting rid of it.....

 

[AronSearle]

I don't think the insulation will do any harm "itself" (some people are apparently allergic to timber, so I don't take much stock in people having allergic reactions to X).

The potential risk from such insulation is...

1. Moisture gets in the wall from the outside, you no longer have a cavity, so where does it go? If the outside surface of the wall and openings such as windows are well sealed, this may not be a concern outside of sever weather areas.

2.Condensation, if you install no vapour barriers in your house, condensation may now form within the wall structure (which may affect old victorian wall ties that are not as rust resistant), I think this is generally unlikely, but it is possible and the company should be able to demonstrate it is not a problem with a condensation risk anylisis.


Beware that there are plenty of cowboys about, there are examples of people with solid walls, where the insulation guys just drilled some holes and pretended, because most householders are pretty ignorant they get away with it.

 

[dishman]

This is not the purple stuff then. That is usually the quick fix spray on stuff done internally.

This is the different expanding foam type insulation pumped in at pressure as you say. I do not know how good it is compared to other types, I watched a few videos on youtube about it.

I am not in the industry, but I would be concerned about the following:

1. How vapour permeable is this expanding foam. Does it dry very rigid and solid? Does it allow the wall breath? Does it/can it transfer moisture or allow moisture to bridge the cavitys?

2.Would there be any issue with the pressure this is pumped in at with an old building? I have seen on videos this stuff sometimes forces itself out through weak points in the mortar. I have no idea if this is ok or not, but it doesn't good!

I do not know the answer to these things myself. These are just the questions I would ask.

 

[boilernoob]

Thank you very much guys for your helpful advice. I'm in two minds as I don't have enough info to know what this stuff is and at the same time I'm thinking winter will be here soon again, so should I get it done or not

I know you must be thinking I'm mad, but so far I've not found a single website saying this is bad stuff...god i don't know what to do!

 

[AronSearle]

Thank you very much guys for your helpful advice. I'm in two minds as I don't have enough info to know what this stuff is and at the same time I'm thinking winter will be here soon again, so should I get it done or not

I know you must be thinking I'm mad, but so far I've not found a single website saying this is bad stuff...god i don't know what to do!

If you have a cavity, get the blown in polystyrene beads, they allow water to drain, almost impossible to fick up with them.

Make sure the people doing it, fill all the areas and don't leave lots of voids.

 

[boilernoob]

Thank you very much guys for your helpful advice. I'm in two minds as I don't have enough info to know what this stuff is and at the same time I'm thinking winter will be here soon again, so should I get it done or not

I know you must be thinking I'm mad, but so far I've not found a single website saying this is bad stuff...god i don't know what to do!

If you have a cavity, get the blown in polystyrene beads, they allow water to drain, almost impossible to fick up with them.

Make sure the people doing it, fill all the areas and don't leave lots of voids.

Thank you AronSearle. How can I make sure that they fill all the areas?

 

[kbdiy]

Your house may well be built with a 'finger cavity', which is just that, about a finger width between the brick skins. AFAIK this type of construction is definitely NOT suitable for any kind of injected insulation, and the thickness would be so small as to give no perceptible benefit anyway.

The salesman is a muppet. Tell him to go away.

Incidentally, it's worth goggling 'finger cavity'. The results have nothing to do with buildings but the YouTube link about a Texas policeman is well worth it

 

[boilernoob]

ROFLOL! Thats a shocking video

 

[dishman]

Another option is to get a local chartered surveyor to come an inspect the cavity and assess its sutibility for wall insulation. You could even just speak to them and get their opinion.

At least that way you would independantly know the size of the cavity yourself. Some surveyors do not recommend insualtion at all, but they may be able to advise on material types.

I found this rough guide:

http://www.yorkshireinsulation.co.uk/cavity-wall-insulation-options.html



Can you try to estimate the cavity size yourself? At a doorway or window reveal. find somewhere where you can measure the thickness of your outer stonework, the thickness of the inner brickwork and then the full thickness of the wall. That way you should be able to work it out.

 

[boilernoob]

According to the link you provided, it says that Polyurethane insulation is:-

Not to be confused with the now banned Urea Formaldehyde foam, Polyurethane foam is a form of wall insulation that can be suitable for 'random stone' walls or other properties with non-standard cavities. It has excellent thermal properties and with a “closed cell" structure it is totally water repellent.

I've got a rough measurement...although different sizes for front and Rear walls

Front wall - total wall thickness is just over 25cm
Rear wall - total wall thickness is 30-32cm

The external stones and internal bricks have a regular pattern

From looking at this site (bottom of page, it seems that I may after all have a cavity -

http://ecogreenrenovations.co.uk/solid-wall-insulation.php[/b]