Spray foam removal

boongywoongy

Just seen a bungalow that we like, however, it has spray foam insulation in the loft which was installed 15+ years ago. 

Can I remove this as a DIY project or does it have to taken out by a professional? Obviously, I would take the necessary breathing precautions etc.

stuart45

You can do it yourself if you want. 

boongywoongy

Do you know the tools that I need? Is a multi tool and wall paper scraper Ok or do I need to hire some dry ice blaster? 

Albermarle

boongywoongy said:

Just seen a bungalow that we like, however, it has spray foam insulation in the loft which was installed 15+ years ago. 

Can I remove this as a DIY project or does it have to taken out by a professional? Obviously, I would take the necessary breathing precautions etc.

If it has been there for 15 years and not caused any problems, do you need to take it out?
Have you had a look in the roof, at the timbers etc ?

bryanb

Try doing a small area - You may change your mind. 

TELLIT01

There were stories a couple of years ago that financial institutions wouldn't give mortgages on properties with spray foam roof insulation.  Does your potential provider know about it?

We had spray foam done over 30 years ago on our property and there have been absolutely no problems with the roof.

stuart45

boongywoongy said:

Do you know the tools that I need? Is a multi tool and wall paper scraper Ok or do I need to hire some dry ice blaster? 

You can use a long knife with a serrated edge or a saw to cut into it. You need to be careful not to cut into the felt. 
It's a lot of work, which is why it's so expensive. 

tacpot12

It's not a job I've done before, but I would imagine that it would be easiest and safest to use a pry bar and hammer to chip the foam off. This sort of pry bar: https://www.screwfix.com/p/magnusson-utility-bar-15-/4594V

Use the hooked end dig into the foam so you can break out large chunks with light blows from the hammer.

This will probably work better if you can first cut down the rafters so the foam is only stuck to the roof covering. A reciprocating saw might be a good tool for this, especially if you can find a very short blade such that it can't touch the roof covering as you run it down the side of the rafters. 

Aiming to do a small area is a good idea. Doing so allows you to refine your technique. 

Invest in good masks, like this one: JSP Force 8 Medium Mask Respirator with Press-to-Check Filters P3 - Screwfix

It might be worth boarding over the loft temporarying as this will prevent accidents - you don't want to fall through a ceiling and add another job to your list. The boards can be lifted later and refitted over improved insulation using a LoftLeg or LoftZone kit.   
 

boongywoongy

All fantastic comments. Thank you.

So the property seller is aware of the current mortgage lender problems and spray foam insulation problems and has priced it accordingly.

We are very tempted but need to be sure that we can either remove the foam or afford to get it taken out professionally so as not to affect future resale value.

Can anyone give an idea of the removal cost?

stuart45

It depends on the size of your roof, but usually about 3or 4 grand.

ThisIsWeird

BW, where is the foam? I presume on the sloping roof, so in between the rafters? And not on the floor - the ceiling of the house below?
(How do these companies get away with this? Adding insulation to the underside of the roof contributes zero to the heat retention of a lofted house.)
Anyway, assuming that the roof members made at risk by the presence of foam are the actual rafters, is there mileage in just cutting away a wedge-shaped trough adjacent to them? Eg, carefully slice down firmly against the rafter sides until you make contact with the underfelt, and then slice at a ~45o angle into the foam, sloping towards the rafter's side, at a distance from the rafter at whatever equals the foam thickness. Then prise out this foam toblerone. The rafters should then be both examinable and fully ventilated, and no foam needs to be scraped away from the actual felted areas in between. It should look quite neat, and not the complete mess full removal would be.
Perhaps also V-cut the odd horizontal channel down to the felt layer, to monitor and detect if any rain is running down the felt from a leak?
Would that work? Ie, what harm is being caused to the main foamed felt - can't that be left?