Cold Roof Insulation Between Joists

Cold deck roof a cold deck roof is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof.

Cold roof insulation between joists.

Easily the most frequently asked question to the celotex technical centre is with reference to hybrid flat roofs. Ventilation is required for these roofs. A cold roof is where all of the insulation is placed either between and under or completely under the joists or deck. Where insulation depth is restricted by the flat roof construction it may be necessary to install the roof insulation between and below the joists to create a cold deck structure.

In this way the roof itself is kept cold. You only need ventilation in a cold roof. I intend to fill between my joists with foil backed insulation board 75mm with a thin layer of insulation on top of the joists. 2d extend insulation into joist space to reduce air flows.

In this context the term hybrid flat roof refers to a timber flat roof construction that is insulated both between and over the joists. In finished attic rooms with or without dormer insulate 2a between the studs of knee walls 2b between the studs and rafters of exterior walls and roof 2c and ceilings with cold spaces above. The insulation is below the deck but above the plasterboard. Cold roofs by the way are not recommended for high humidity areas see the blog on how to insulate.

Introduction warm cold roofs this guidance offers guidance on the difference benefits between warm and cold roofs. Guidance advice on. No insulation is on top. Increasing your home s value.

Improving your home s energy efficiency rating. This is used for refurbishment e g. Other benefits of roof insulation include. Warm and cold roofs for insulation purposes.

Poly to the underside of joists. A cold flat roof is one where the insulation is between or between and below the roof joists. Refurbishing an existing timber joisted flat roof which has no insulation. This quetion is to do with warm roofs and cold roofs presumably the 50mm of insulation on the underside of joists would act as the vapour barrier if taped sealed correctly or if insulation between joists a vapour barrier i e.

As for insulating below the joists an insulating laminate insulation bonded to plasterboard such as celotex pl4000 or a separate rigid pir insulation board finished with a separate sheet of plasterboard can be securely fixed to the joists to provide an internal finish to the roof. Insulation between the joists keeps warmth in your living space below and creates a cold loft while insulation in the rafters allows you to keep warmth in the roof space as well. Great videos thanks for sharing. This method of insulation can also be used to upgrade the thermal performance of an existing roof without affecting the waterproofing system.

I ve built a timber frame to support a new plasterboard ceiling below the existing one.