Insulation, Eaves and General Warmth

[tsomo2000]

Hi All

I am looking for a bit of advice. I currently live in a 1970's built 2 floor semi, with flat roofs above the upstairs bedrooms (front and back) and I have eaves above the ground floor (see picture).

The house itself is very cold. As you can see there has been a bay window extension at some point in the last 10 years, but unfortunatley the bay window hasnt been fit correctly, the ceiling of the bay is straight on to the bottom of the eave, and the radiator for the room is underneath the window. All the heat generated from the radiator goes straight up and dissappears it takes an age for the room to get to any sort of temperature, and i still usually have a hoody on for warmth. The ground floor itself is also open plan with doesnt help (living room into dining room with large doors on to the back garden). The bay window is also poorly fitted, i can get my small finger into a gap and into the eave so it is very draughty, i could probably push the window out if i gave it a good push.

Firstly I am going to try and fix the bay window in a more sturdy manner, and seal where relevant, and then insulate the eaves. To insulate the eaves am I ok to use standard loft insulation, or would something like Kingspan be more suitable?

I was also thinking of bringing the ceiling down on the ground floor and insulating between floors with 100mm Kingspan, would this be a good idea or with it stop the natural warmth rising through the house to the 2nd floor?

Along with this I am hoping that resiting the radiator (a new double finned one) to a different location within the living room, and the addition of some french doors between the living room and dining room with hopefully give me some more warmth.

By the things that I have found around the house, it has been a bit of a DIY'ers paradise, unfortunatley the DIY has been to a poor standard.

I should also mention that I have had cavity wall insulation installed, and there is some insulation in the loft, however due to the flat roofs above the bedrooms I am unsure if there is any insulation above the bedrooms, I will rectify as and when i decorate the rooms by bringing the ceilings down and insulating with kingspan (if recommended)?

(open plan living room to dining area - sorry about poor picture)

Thanks

Alex[/img]

 

[jeds]

Is there room to insulate that bay window from inside - i.e. add a thermal lining to the ceiling?

The radiator also looks undersized to me. A double panel convector from B&Q wouldn't cost much more than fifty or sixty quid and would probably double the output. I personally wouldn't move it to another location. The bay window would then just become a serious cold zone and would probably end up more uncomfortable than it is now. Far better to solve the insulation problems and leave it where it is.

PUR foam type insulation (Kingspan, Celotex etc) has approx double the insulation value of mineral wool, but is more expensive. The general rule is; if you have room for a good thickness of mineral wool and good ventilation over the top then use it. Otherwise look at PUR foam, but you must be careful of condensation.

Top of the general loft insulation as much as possible and check the flat roofs. I'd say there's a very good that the flat roof insulation is lacking.

Insulatiing the ceiling might make the room warmer but isn't going to do anything for the general house warmth. Seems like a lot of work for not much gain to me. Unless you have noise transfer problems. It would be good for that.

 

[mointainwalker]

If you are happy with a cold bedroom, it might be worthwhile to insulate between floors because the downstairs, where you probably spend 95% of your waking time, can be made that much warmer for the same heat output.

 

[tsomo2000]

unfortunatley there is no room to insulate the ceiling above the bay window, the top of the window sits directly on the eave ceiling.

The bedrooms upstairs have quite good radiators so the rooms get quite warm, i believe with some proper insulation in the flat roof then this should improve the situation.

The reason i spoke about insulating between floors is I have a source that can get me Kingspan insulation very cheap (7sq metres for £90), however i have to factor the price for a new ceiling (any ideas?), and if it keeps the room downstairs a lot warmer then it keeps the other half happy, which causes me less stress!

 

[mointainwalker]

I note that you speak about insulating the eaves and also mention the ceiling insulation.

There is absolutely no point at all insulating the eaves ( between the rafters) unless you want to spend a lot of time up there. as in loft conversion.

If you are living on two floors, ensure that you have a vapour-barrier (poly sheet) draped over all of the surface of the floor in the loft (bedroom ceiling) and then put down as much fibre-wool as you want/can ( except under any water-tanks)

 

[ajrobb]

As you can see there has been a bay window extension at some point in the last 10 years, but unfortunately the bay window hasn't been fitted correctly, the ceiling of the bay is straight on to the bottom of the eave, and the radiator for the room is underneath the window.

I assume you will take down the ceiling in the bay to give access to the rafters. You should leave an air gap of 50 mm under the tiles. This probably limits you to 50 mm of Celotex between the rafters flush against the new plasterboard. Don't expect too much though, the ceiling is small compared to the windows. Unless there are leaks in the ceiling, the large windows are probably already loosing more heat than the ceiling.

The radiator looks inadequate (a P1) for a 1960's house and I think that might be the main cause of the problem. I'd replace it with a K2. Put reflective foil behind the radiator to reduce the heat pouring out through the wall. Put a shelf over it to deflect the warm air away from the windows (keeps them cleaner too).

As the house feels cold, I wouldn't move the radiator from under the window. That would cause circulating drafts and make you more uncomfortable!

Have you gone for cavity wall insulation yet? As long as you aren't exposed to driving rain, the subsidised mineral wool insulation should help.

Can you see into the flat roof voids from the loft? You might be able simply to push 50 mm Celotex between the joists to insulate the dormers. Otherwise, I'd take down the ceilings and insert Celotex from below. Again leave 50 mm above the Celotex for ventilation. I doubt you've got the ceiling height to stick Kingspan under your existing bedroom ceilings.

I've had various quotes from roofers to insulate our flat roofs and they seem to suggest a 'warm roof' solution - putting 100 mm of rigid insulation above the existing flat roof with marine ply then felt on top. Expensive though.