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Loft Conversions
Loft boarding and insulation - raising floor, laying 100mm thick insulation on top of existing insulation, then board onto it.
Hi, I am looking to create some storage space in my loft and also insulate it correctly. Currently there are some lose boards laid down randomly and insulation in-between the ceiling joists.
My plan is to board a small area (7-8m2). I was planning on raising the floor in this area using 2x4 running 90 degree to the existing joists and then lay 100mm thick insulation on top of the existing insulation, then board onto it. Then the remainder of the loft I was going to lay some 200mm loft insulation overlay.
Does that sound ok? also should I put the overlay on top of the pipes from the water tank or just leave that area with the single insulation (I don't think there is room to put any more under), same question goes for the stink pipe. thanks
Additional
Hi Andy, thanks for the reply. Haven't considered using Kingspan. If I go down that route do I just lay that over the rafters and secure with screws then just board straight onto it? Again using screws to secure it?
3 Answers from MyBuilder Loft Conversion Specialists
Best Answer
你需要270毫米insulation, so raise the joists using iso 175mm stilts or equivalant. The boarding and stilts are only designed to take a maximum of 50kg per sqm storage.Leave the area under the tank at 100mm. Dave Bishop
Answered 30th Oct 2014
Hi,
Firstly you should check that the loft can take the additional weight of the 2" x 4" timber. The correct method for insulating the loft is to lay insulation in between existing joists and then lay additional insulation across at 90 degrees. The Building Regs ask for 280mm of mineral wool but there are other products that have better thermal efficiency and a price tag to match. Make sure that you retain any air flow at eaves or condensation may form in the loft and cause problems. If you intend to board some of the loft then I would consider using kingspan or celotex between and then board over the top and use mineral wool everywhere else. Check with building control if you have any doubts.
Best wishes
Andy at Room-by-Room (UK) Ltd
Answered 24th Jan 2014
Hello, We can spray foam insulate the main roof creating a warm, dry, pest & draft-free environment. We use a soft breathable foam that adheres to the loft membrane or felt. We do not spray tiles. This way the loft space is a similar temperature to the home and you will not have to raise the floor at all. We would board over the current rafters providing they are in good order. Our spray foam solution, not all gives you good thermal resistance it completely stops cold air-infitltration and warm air leakage.
Answered 8th Mar 2021
