roof spray insulation

[Ivan_England]

Hi,

 

What is people's general opinion on spray insulation, and is it worth the cost? Also how much should it be? I have had one quote that seems rather high (in my opinion). Was £2.5k for a 49m2 roof. Would love to know your thoughts. Thanks

[Onoff]

Is this that retro fit stuff that claims to sort all your draught, leak and loose tile issues?

[Ivan_England]

Hi,

 

Yes exactly. So people say it also really helps with air tightness. 

[A_L]

@Ivan_England, You have not said how thick it is to be, but assuming 25mm, DIY kits can cost £8-10m² , https://superfoam.co.uk/index.php/hikashop-menu-for-categories-listing/product/128-foamseal-600-diy-kit?_ga=2.26863357.1527463307.1592643557-382492703.1592643557 so your £50m² might be a bit high for installed.

 

At 25mm you would be adding 1 R unit of thermal resistance and it would not be worthwhile for this alone. If the foam would be part of an air tightness envelope for the whole building it would improve the viability but not if there are other significant air leakages.

[makie]

You also have to consider how your attic will be ventilated after.

[Onoff]

I've seen this advertised as the solution to a poor condition roof with slipping tiles, slates etc. 

 

Thinking it might make it a pig of a job if you do ever decide to replace the roof covering (if its all stuck together).

[Ivan_England]

  On 21/06/2020 at 00:26, Onoff said:

I've seen this advertised as the solution to a poor condition roof with slipping tiles, slates etc. 

 

Thinking it might make it a pig of a job if you do ever decide to replace the roof covering (if its all stuck together).

Expand  

Yes, I think by the sounds of it isn't worth it. To insulate the ceiling of the roof, is about £300 so I think i'll stick to that. 

 

Thanks

[MAB]

I saw a house recently that had a dormer roof loft conversion added after the old tiled roof had been spray insulated a couple of years earlier by the previous owners (to me it is a temporary bodge job in most cases). The builders had a nightmare removing the old roof tiles and the whole road was littered in foam insulation carried around on every gust of wind.....