Loft insulation

lindatoo

Just had my boiler serviced and asked the plumber to take a quick look at my loft insulation whilst he was up there. His view was it wasn't anywhere near thick enough so I'm currently gathering info on costs and best type of insulation for a pretty standard 3 bed semi. Any advice welcome.

ic

Last winter I topped my loft up to 300mm depth.  For a modest 3 bed detached house I needed five rolls of 170mm insulation.  Took me an evening to put in place myself, cost about £100 to do (but taking a quick look, prices are higher now... - but still worthwhile!).  I also bought a pack of loft boards so I could move around.

I used Knauf Eko from B&Q - it wasn't itchy.  However I inevitably came into contact with the existing insulation which was.  Get a face mask, as its dusty work.  Be sure to roll it in the opposite direction to what you already have, so as to minimise gaps - and don't block airflow at the eaves.

lindatoo

ic said:

Last winter I topped my loft up to 300mm depth.  For a modest 3 bed detached house I needed five rolls of 170mm insulation.  Took me an evening to put in place myself, cost about £100 to do (but taking a quick look, prices are higher now... - but still worthwhile!).  I also bought a pack of loft boards so I could move around.

I used Knauf Eko from B&Q - it wasn't itchy.  However I inevitably came into contact with the existing insulation which was.  Get a face mask, as its dusty work.  Be sure to roll it in the opposite direction to what you already have, so as to minimise gaps - and don't block airflow at the eaves.

Thank you I will check it out, one of my concerns is the reports that some types of insulation can cause damp. I have a company coming round tomorrow to give me a quote for the spray on stuff, but I seriously think that it will be well beyond my means.

Apodemus

With regards to the spray insulation...  Don't!  Just DON'T! 

Jonboy_1984

If you look around the forum a bit there are very recent threads where mortgage companies (or the surveyors they appoint more correctly) value properties at zero if spray foam is fitted as it often used to conceal damage, or is often badly/inappropriately fitted and results in roof issues.

Roof then potentially needs almost full replacement to correct.

£100 to £150 quids worth of rolls from b&q is the way to go.

lindatoo

Apodemus said:

With regards to the spray insulation...  Don't!  Just DON'T! 

Really? I'm sure you have reasons and I would be most interested to hear them, but even without the reasons I am thinking 'maybe not then'

lindatoo

Jonboy_1984 said:

If you look around the forum a bit there are very recent threads where mortgage companies (or the surveyors they appoint more correctly) value properties at zero if spray foam is fitted as it often used to conceal damage, or is often badly/inappropriately fitted and results in roof issues.

Roof then potentially needs almost full replacement to correct.

£100 to £150 quids worth of rolls from b&q is the way to go.

Following the comments from @Apodemus I googled it and I'm going to cancel tomorrows appointment. Thanks to you both for the warnings

Apodemus

Maybe I'm overly negative on it, but there is a more balanced review here: https://www.youtube.com/watch?v=jYNufQVIFfA

lindatoo

Apodemus said:

Maybe I'm overly negative on it, but there is a more balanced review here: https://www.youtube.com/watch?v=jYNufQVIFfA

I love this guys videos and have seen a few of them not that I'm much of a DIYer but he does explain how things work, and whilst he did give a balanced overview it was still enough to make me more convinced that spray insulation is not for me. Thank you.

FreeBear

Jonboy_1984 said:

If you look around the forum a bit there are very recent threads where mortgage companies (or the surveyors they appoint more correctly) value properties at zero if spray foam is fitted as it often used to conceal damage, or is often badly/inappropriately fitted and results in roof issues.

Roof then potentially needs almost full replacement to correct.

Add to the list the outgassing of cyanide compounds as the stuff cures. Should it ever catch fire, even more toxic fumes will be released, and the roof will go up like a roman candle.

If the roof ever springs a leak (from a slipped tile perhaps), the water could pool beside one of the roof timbers unnoticed for a very long time. In the process, the timber will be quietly rotting away, and the first sign of trouble will be the roof sagging or even collapsing. In the process, dry rot may take hold which could lead to even more trouble.

Arfa__

Another shout for the B&Q Eko Roll DIY route, especially if access into your loft is straightforward. Just done this in my house, it was a pretty big 6-bed house, needed around £500s worth in the end, and rolled it out in sections over a few weekends. After shopping around B&Q was the cheapest, and they still have 200mm rolls going for £25 a pop. But do also check out the B&Q Club, you might be able to blag a bit more off (they occasionally do a 10% weekend). The rolls are bulky, you won't get many in a car, so might be best to order online for delivery.

Def get some gloves and masks. A boiler over suit is a good plan too. A long pole or rake can be handy to push it into any tricky corners.

Just ensure you leave adequate ventilation at the sides, so air can flow through the loft. Also, if you have downlights, best to make sure they have suitable covers to give them room and not-overheat. Google 'loft lids' - Wickes do them, but they're cheaper online at LBS Builders Merchants. We had loads of downlights, none had proper covers, no wonder some looked a little blackened when I swapped out all the 50W Halogens in them...

We only had about 160mm of insulation (up to the top of beams) originally, I put in 200mm on top, and immediately noticed a big difference even over the last couple of months, house now retains heat so much better. Hoping it'll make a decent impact on winter gas usage. Sure 270mm is the recommended minimum these days, just didn't seem worth going through all the hassle of laying it to put just this minimum, and 200mm rolls weren't much more (a quid more for slightly shorter lengths).