Non-destructive ways of finding out if you have cavity wall insulation

Section62

Chickereeeee said:

ris2015 said:

Check top of wall from inside your loft space.

That's my suggestion. I can put my fingers down the gap there in mine. 

Unfortunately that method:

1) Relies on the cavities not being closed.

2) Relies on the cavity being filled to within finger-length of the top

3) At best only gives an indication of what the situation is at the top of the wall.

Ergates

OK, so earlier today I drilled a couple of holes in different places in the wall and put an endoscope through and...

just empty space.   So, it appears we don't have cavity wall insulation.

Thanks all for the tips and suggestions.

stuart45

What size cavity have you got?

Ergates

stuart45 said:

What size cavity have you got?

That I don't know.  Not sure how to measure that either.  I can measure the depth from the surface to the surface of the 2nd layer, but I'm not sure to how work out how much of that is air.

stuart45

The block will probably be 100mm and render around 15mm, so the rest will be the cavity width. You could also measure the overall thickness of the wall at the door frame.

FreeBear

A 20 year old house will be built using modern metric sized bricks - These are (nominally) 100mm wide. If you have render, allow another 15mm or so. Shove a sick into the hole, measure how far it goes in, and then subtract 115mm - That will get you within +/- 5mm.

Ergates

And today I learned something new:   We live in a area with "very severe" wind driven rain (west cost of Scotland - sounds about right), which means our homes are not suitable for standard cavity wall insulation as it can cause penetrating damp.  Which at least explains why it wasn't installed when the houses were built.

We'll still get the opinion of a professional - there may be there are some methods that are suitable for where we live (polyurethane foam perhaps).  They'll probably be several times more expensive though.

stuart45

Normally in an area like that a part fill insulation board is used, leaving a 50mm clear cavity. To meet the U values a thicker inside AAC block might of been used.

Ergates

stuart45 said:

Normally in an area like that a part fill insulation board is used, leaving a 50mm clear cavity. To meet the U values a thicker inside AAC block might of been used.

Yeah, I saw something like that in the regs.   But when I put the camera in what I saw looked like more concrete/cement blocks (a rough surface) and felt hard when I was poking it with the drill bit.

Chickereeeee

Section62 said:

Chickereeeee said:

ris2015 said:

Check top of wall from inside your loft space.

That's my suggestion. I can put my fingers down the gap there in mine. 

Unfortunately that method:

1) Relies on the cavities not being closed.

2) Relies on the cavity being filled to within finger-length of the top

3) At best only gives an indication of what the situation is at the top of the wall.

Then you can drop the endoscope down (if its not 1). Drilling a hole only gives you the situation at one point.