Hello All,

I have joined this forum today. I have been reading postings oin this forum for quite sometime now and finally i got time to share my house renovation problem.

I have lived in this detached 4 bedroom dormer house (buit in 1968) since october 2005. I moved in this house in 2005 winter, it was very cold even when we had central heating on for 24 hours, which increased my gas bill to almost £200 a month. This house didn;t have cavity wall insulation, i got this done in january 2006. Soon after that i got central heating quote and got whole of central heating replaced (indluing all old radiators). After getting new central heating installed, i thought my gas bill would reduce drastically as i have condesning combi Worcester Greenstar Highflow 440 instaled now. But contrary to my imagination my monthly gas bill is still close to £150 a month, but i must admit this house has become habitable now.

I was reading on internet that if i have undefloor heating done it will reduce my gas bill further as ambient temperature for UFH is only 19 degree compared to 21 degree for convetor heating. I am told my my ocal building inspector that i will have to use 50 mm underfloor celotex insulation because i have suspended timber floor. I have decided to exceed this isulation requirmenet and put 100 MM celotex insulation board. I have been told that wet under flor pipes should be cliped on celotex insulation between timber joists. And to increase thermal mass i should use 25 MM sand and cement screed to cover UFH pipes which will keep the floor warm for longer duration.

My question relating to Under floor heating is that does it really reduces energy requirements ? will 19 degree will be ambient temperature if i have UFH? Do i ned a joiner or a builder to put these insulation board and UFH pipes ?

My Next worry is that i on first floor carpet floor gets really cold because and in windy days carpet gets lifted upto 1/2 inch due to wind coming between ground floor roof and first floor flooring. i had roof repairer coming and they claimed that they fixed the problem by changing felt. BUt i can still feel the cold air coming under my first floor carpet and whole carpet is very cold. though OVERALL TEMPRATURE goes tro around 21 to 22 edgre when we have our central heating on.

Both side of my house has dormer roof which is below window. I have feeling that both sides dormer roof need repairing. Do i need this dormer roof repaired from inside or outside?

Both side of dormer has not got brick wall but rather it has plaster board which is very very cold in winter.

DO i need to get both side of dormer roof changed ? Behind this dormer roof there is only single brick wall.

What is the best method to achieve below 1 U value for my house?

Do i need to contact a structural engineer or an insulation consultant ?

Because one side of roof felting was repaired by a local roofing company and charged me £700 and said he has insulated external wall so to prevent any wind coming under my first floor. This company gave me 10 years gurantee and i rang them to complaint that I still have wind coming through my floor and i was told that this
roofing company is no longer in business now.

Is it norma to leave ventilation for joists on the first floor between ground floor roof and first-floor floor?

I have my roof well insulated with fibre glass. Do i need to insulate inside of roof frame with celotex board?


My house is on seaside and its very windy in winter.

I am quite reluctant to contact local builder before i really know what needs doing in my house.


I will be grateful for your help and advice.


Thanking You al in advance.

Regards

Niraj

I'll agree with all of that.

Hello, Frank, Mike and Nigel,

Thank You very much for your comments. I am delighted to get such a good response.

I am glad that i joined this forum which saved me £XXXX on UFH.

Do you think i can draught proof the house myself ? If yes what materials i have to use to seal air ingress on first floor void ? IS IT A DIY Project ? Can i do it from inside or do i need to take dormer tile off and insulate it from outside?

Why my foor temperature is always 2 degree less on ground-floor floor compared to tremperature at 6 feet height on the same foor? Has it got something to with my big georgian front door (with side panel) which is not double glazed?

I am contemplating getting this big front door changed into triple glazed. ANy feedback of triple glazed windows and doors ? i have read that triple is still the same thinkness 28 mm with k glass but it is more effective. I want to be future proof thats why i want to use triple glaze. but it is expensive compared to double glazing ANy feedback on triple glazing?


Thanking ou

Regards

Niraj

Hello Nigel,

Thanks again. I can get access by removing all carpets and wood floor on the first floor. because one side of dormer is only windows in three bedrooms and other side is bathrooms, landing, cupboard and ensuite which is not that bad but will get them draught proof once i start chaging bathrooms and ensuite.

What materials should i use for draught proofing ?

My current ground floor insulation is around 5-10 mm under chipboard. Do you think i should just upgrade this to 100 MM celotx insulation board? will that help and ofcourse will have th draught proof dromer walls and first floor void?

Need to know what materials can i use easily for draught proofing ?


Thanking You

Kind Regards

Niraj

What I would do is to go upstairs and figure out which way the floor joists run. They run at right angles to the floorboards or flooring panels. Starting of in one room, go to the outside wall where the ends of the joists go into a wall. Lift the board or panel and inspect the seal of the mortar around where the joist go into the wall. If there is a gap squirt some sealer into the gap. If its very big, stuff the hole with old plastic bags then use sealant. At the same time look at the seal around any pipes or wires. Do the outside end of all joists. As mentioned, there will be a joist that runs about 2" from an outside wall, try and stuff this gap with WHY (glassfibre / plastic shopping bags. . . ). One good target would be the waste for the bath. sometimes they are drop down from the bath, theres a huge hole in the floor and the pipe then runs through another big hole(in the inner wall skin), to the outside where the pipe is neatly mortared in, cos it can be seen.
Frank

No way should you need an engineer! If you felt the need a surveyor could be the person you need to help you with specification. Take lots of photographs of everything and new work and inspect everything before is is covered up again. Building control is likely but they dont care much more than lip service about air infiltration. Keep a very close eye on the work. Badly fitted sheet insulation can do less insulating than quilt because of the disproportionate effect of gaps.

You must finish up air leakage free especially from outside to under the floor. There is little point in having expensive insulation in the walls if there is a howling gale from outside cooling the floor and the room. It probably blows out from under the skirtings even on internal walls!