In the latter case where the insulation follows the rafter line there are many different ways of constructing the roof.
Roof dry valley construction.
In many ways the roof construction for a pre formed grp valley is the same as that for a lead lined valley.
A roof valley is formed where two roof slopes meet.
Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks.
The pitch of the roof here is 35 degrees the untiled main slope of the roof is 45 degrees.
Many of these warm constructions include a requirement for counterbattens below the slating or tiling battens.
If your roofing contractor can he will get rid of the metal which means you don t have to pay for it while installing a roof valley.
Valleys are typically found where gable dormer roofs meet the main roof or when a house has angled wings or additions where two roof sections in different planes meet.
It is therefore worth asking the valley manufacturer for guidance on this.
The dry valley mitred at the ridge and awaiting the final tile course.
Essentially there are three main ways to shingle a roof valley.
For an open valley a sheet of metal usually steel sometimes copper is fastened to the roof deck.
Water collects in a valley to flow off the roof.
Redland dry valleys are suitable for both traditional cold roof and warm roof construction.
Either lay tiles dry or bed on mortar onto fibre cement undercloaks laid loose on each side of valley ensuring a minimum 25mm gap between mortar and the tilt fillet.
Open valley troughs have been designed as an alternative to traditional lead troughs a safe and efficient way to collect rainwater run off.
Also keep in mind that at times open valleys are prone to storing water and thus causing roof leakages.
Cut tile and a half tiles neatly and fix to form a gap minimum 125mm wide centred on valley.
Roofing shingles are installed then cut and sealed where they overlap the metal channel.
No one but you can decide which kind of valley you want for your roof.
Some grp valleys are sufficiently robust to enable them to be laid directly over the rafters rather than being supported on valley boards.
The metal is usually pre painted to best complement the shingles color blend.
Dry fix valley troughs are mortar free providing hidden water gulleys at the roof valleys.
Alternatively a tile and a half may be used to avoid small cuts of tile.
Additional eaves closure pieces and counter battens are not required and they create a close cut appearance.
In this situation the bridge piece is placed in position to support the smaller cut tile section.
Woven closed cut and open.
