Roof insulation

ACVC2006

Hi 

should I consider insulating my roof? I live in a 3 bed detached home. 

FreeBear

ACVC2006 said: should I consider insulating my roof? I live in a 3 bed detached home. 

No. You need to insulate the loft. 300-400mm of fibreglass or mineral wool between & above the ceiling joists. That should cut heat losses by ~25% and reduce your heating bill considerably.

Just do NOT fall for bogus claims for spray foam insulation - Totally inappropriate for any/all buildings not designed for it from the outset. It will also devalue your house when it comes to selling or remortgaging.

ThisIsWeird

A bit more info, please, ACVC.
What do you mean by 'roof'?
What sort of loft space do you have - exposed rafters?
What sort of insulation were you considering?

ACVC2006

FreeBear said:

ACVC2006 said: should I consider insulating my roof? I live in a 3 bed detached home. 

No. You need to insulate the loft. 300-400mm of fibreglass or mineral wool between & above the ceiling joists. That should cut heat losses by ~25% and reduce your heating bill considerably.

Just do NOT fall for bogus claims for spray foam insulation - Totally inappropriate for any/all buildings not designed for it from the outset. It will also devalue your house when it comes to selling or remortgaging.

Thank you for responding- can I ask why the loft and not the roof please? I do intend to use it for storage. 

ACVC2006

ThisIsWeird said:

A bit more info, please, ACVC.
What do you mean by 'roof'?
What sort of lift space do you have - exposed rafters?
What sort of insulation were you considering?

Sure. By roof I mean the part under the roof slates. Do I need to insulate it if I intend to use the loft for storage. The rafters are not exposed but there is some sort of underlining beneath because of which I cannot see them or the roof tiles. I am not sure what sort of roof insulation should I consider? I am not a DIY pro and don’t have much knowledge about these things. 

stuart45

Have you got any insulation between the ceiling joists?

ThisIsWeird

ACVC2006 said:

ThisIsWeird said:

A bit more info, please, ACVC.
What do you mean by 'roof'?
What sort of lift space do you have - exposed rafters?
What sort of insulation were you considering?

Sure. By roof I mean the part under the roof slates. Do I need to insulate it if I intend to use the loft for storage. The rafters are not exposed but there is some sort of underlining beneath because of which I cannot see them or the roof tiles. I am not sure what sort of roof insulation should I consider? I am not a DIY pro and don’t have much knowledge about these things. 

Could you take some photos, please?

In a conventional loft, you go up through a hatch, and usually find exposed joists on the floor, which is what holds up the ceilings below. These are often boarded out to make useful storage space. It's there that you add loft insulation as FreeBear was saying, and this helps to keep the main house cosy.

Then, in most lofts, when you look at the underside of the roof, you will see similar timbers to that of the floor joists, but obviously at a sloping angle to match the roof - these are rafters. These are usually exposed, and the loft area is well ventilated - draughty - to keep all that timber dry.

You can board - or 'line' - out these slopes too, but it must be done correctly, or else you run the risk of preventing the flowing air from keeping the rafters dry. 

So, we need to know what you currently have, and what it is you wish to do.

Bear in mind a couple of things; most open ventilated lofts like I described above are draughty and cold, but they are dry as a result; you can usually store things up there quite safely. And, adding insulation to a room does not, in itself, make it 'warm'. For warmth, you need a heat source. If you add a heat source, you need to control the ventilation so you don't lose the heat. If you reduce ventilation too much, you run the risk of damp (a simplified summary :-) )

FreeBear

ACVC2006 said:

FreeBear said:

ACVC2006 said: should I consider insulating my roof? I live in a 3 bed detached home. 

No. You need to insulate the loft. 300-400mm of fibreglass or mineral wool between & above the ceiling joists. That should cut heat losses by ~25% and reduce your heating bill considerably.

Just do NOT fall for bogus claims for spray foam insulation - Totally inappropriate for any/all buildings not designed for it from the outset. It will also devalue your house when it comes to selling or remortgaging.

Thank you for responding- can I ask why the loft and not the roof please? I do intend to use it for storage. 

Lofts are designed to be unheated and draughty. If you insulate between the rafters, you need to stop cold air from getting in. This leads to damp and possibly rot of the timbers.

When insulating the envelope of a building (or any other object), insulation needs to be added at the point where heat loss occurs. In a loft, this is at ceiling level. If you insulate at roof level, heat from the rooms below will warm the loft space and eventually dissipate to the outside - Absolutely zero point in having a warm loft as it is uninhabitable, and the roof provides a much larger area for heat to escape through.

Accept that the loft space will be cold & draughty, and insulate at ceiling level - You will require less insulation to do so, you won't be wasting energy heating an unused space. Both of which will save you money.

Albermarle

A timely article on the BBC news website.
'Spray foam insulation ruined our house sale' - BBC News