Given the massive rise in energy bills coming, insulation is going to lead to much bigger savings on energy bills. Yet our loft is low and so I have a rather unusual issue - I can't insulate it to 270mm.
I have just a 100mm cavity between the joists in our loft and insufficient height to raise the floor. Given there is also a 100mm cavity in-between the rafters, I could add a further 50mm there with sufficient ventilation above.
In terms of heat loss - is 100mm of joist insulation + 50mm of rafter insulation equivalent to 150mm of joist insulation, or basically the same as 100mm of joist insulation?
I have just a 100mm cavity between the joists in our loft and insufficient height to raise the floor. Given there is also a 100mm cavity in-between the rafters, I could add a further 50mm there with sufficient ventilation above.
In terms of heat loss - is 100mm of joist insulation + 50mm of rafter insulation equivalent to 150mm of joist insulation, or basically the same as 100mm of joist insulation?
