For further information on how to construct a watertight sub roof download the wienerberger low pitch installation guide here.
Pitched roof sarking felt.
Please note that a minimum of 50mm ventilation is required under the sarking felt while a drape space should be left under a breather membrane.
The roof does not leak at all and there is no signs of there being any moisture coming through but it does trouble me.
Can i or should i do anything about this.
The sarking comfort pir l board has on 1 side a wood fibre underlay board of 35 mm.
The product can be used as a waterproofing coating on asphalt fibre cement sheeting concrete and bituminous roofing membranes.
Til r classic undertile felt is eligible for one warranty for scottish sarking board projects and where it is necessary to provide a safe roosting environment for bats.
The sarking plus pir l boards are already equipped with an underlay felt on 1 side.
It served two main functions.
It can also be used as a vapour retarder in built up roofing.
It also functioned as a secondary barrier to wind driven rain and snow which penetrated under the roof covering as well as potential pests like insects and birds.
They needn t be used in every application and instead their use largely depends on where in the country you are based and what type of construction you are building.
Next article constructing a low pitch watertight roof part 2.
Previous article modern roofing at low pitches.
Iko enertherm alu nf pro.
Pitched roof insulation with undertile felt iko enertherm is used for the thermal insulation of pitched roofs on the rafters or on the trusses.
Of course sarking adds a significant cost.
Roofing felt was introduced in the 1930s.
The original sarking felt on the pitched roof of my 1950 built house is brittle and in a number of places torn right through so that i can see feel the under side of the roof tiles.
It acted as a protective barrier to the house before the main roof covering was constructed.
Thanks to the self adhesive overlap you create a wind and watertight roof in a single movement.
Previously it had been standard practice to underline slate or tile roofs with a mortar filling consisting of sand lime mortar and reinforced with animal hair.
This brings us to a very important technical issue concerning pitched roof insulation and refers to proper ventilation and breathability of the construction.
Ikopro solvent free water proofer is an easy to use bitumen based emulsion for roofs.
The sheeting or sarking felt is laid over the supporting rafters or counter battens and beneath the tile or slate battens.
Sarking boards are softwood boards generally about 150 mm wide that are attached to the rafters of a pitched roof to give extra strength to the overall structure of a building.