Can you put insulation directly on the roof?
The layer of insulation should continue over water tanks but you should not insulate directly underneath – warmth from the rooms below can help prevent freezing. Insulation should be continued right to the edge of the ceilings but it shouldn’t block the eaves’ ventilation.
Is it worth topping up loft insulation?
With loft insulation, there is a law of depreciating returns, which means the first few centimetres of insulation will save you many times the cost of the installation, but each extra centimetre adds less value, to the point where it is no longer worthwhile to add any more.
Should I insulate the underside of my roof?
Preserve The Attic’s Airflow The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams, and the material will block that flow. For the same reason, insulation shouldn’t touch the roof’s underside.
What thickness of insulation do I need?
What Insulation Thickness Do I Need for Flat Roofs? An uninsulated flat roof has a U-Value of around 1.5 W/m2K. When insulating one, you’re aiming for a value of 0.25 W/m2K or less. To achieve this, you should insulate your flat roof with insulation boards totalling around 150mm thickness.
Can you lay insulation over joists?
Lay the insulation over the top of the joists Starting from the furthest point from the hatch, spread the insulation over the top of your joists, leaving no gaps between the strips. When it’s time to start a new roll, butt the edges together, but don’t overlap or compress them too tightly.
Can you put new loft insulation on top of old?
Yes! You can absolutely new insulation over old insulation… as long as it isn’t wet. Energy Star advises as follows: “If it… appears that the insulation [is wet or] has previously been wet, you should look for the cause and repair the problem to prevent a reoccurrence.
Can I insulate my loft myself?
If your loft is easy to access and has no damp or condensation problems, it should be easy to insulate – and in many cases, it is possible to do it yourself. If access is easy and your loft joists are regular, you can use rolls of mineral wool insulation.
How do you insulate underside of roof?
Open-cell spray polyurethane foam or closed-cell spray polyurethane foam (ccSPF) insulation can be sprayed along the underside of the roof sheathing to provide a conditioned and insulated attic space that can be durable and efficient in all climate zones (see Figure 1).
Should roof rafters be insulated?
Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. You can add insulation to the floor; the more the merrier. Just don’t put it in the eaves. Also, make sure the attic is well ventilated.