This lap must be supported underneath by a purlin to be secure and long lasting.
Side lapping roof.
Lay 6 inch wide butyl tape over all horizontally lapping end seams.
Apply side lap sealant if the pitch of your roof is 2 12 or less.
How a side lap joint works.
As with side lap roofing it s good practice to use lapping tape to help create a robust weather resistant joint.
Peel back the release backing to start the application.
Below you will find examples of side lap details for our most popular profile types.
Side lap roofing end lap joints.
This is ideal for lapping because the sealant stays sticky rather than hardening.
The position of purlins at the upper and lower ends of the roof and at the sheet overlaps are the critical points there must be purlin where you need to nail.
Span roofing roof sheets.
If you re installing a metal roof on a home without gutters you can overhang the panels by twice that amount.
On the eave side of the roof aim to overhang the panels by 1 to 1 5 inches.
When two pieces of metal deck with the same profile are adjacent a side lap joint can be used to fasten the two sheets together by overlapping a portion of each sheet by using a side lap fastener.
Purlins must be at the correct centres and size for the material and slope of the roof.
Five rib roof sheets.
10 4 end lapping 52 10 5 expansion 54 10 6 roof overhang with edge stiffener 55 10 7 sheet ends on low slopes 55 11 0 flashings 56 11 1 materials 56 11 2 longitudinal flashings 56 11 3 transverse flashings 57 11 4 flashing at change of pitch 59 11 5 flashing large roof penetrations 59 11 6 flashing small roof penetrations 61.
Ensure that sheets are fitting well at each stage of laying until the final end of the sheet has been laid.
Single lapping is an economical form of roofing because there is just one layer of slate over most of the roof and a double layer just where the slabs overlap vertically.
The disadvantage compared to double lap is that the perpendicular joints at the arrow are simply butted together and so are open to leaks unless they are sealed in some way.
Side overlap is number of corrugations.
For end lap joints a minimum sheet over sheet overlap of 250mm should be allowed for where the sheets lap.
Corrugated roof sheets.
Why a side lap joint matters.
Flow tile and wave tile can only be laid right to left whilst brit tile can only be laid left to right.
Tile effect sheet side laps.
Tile effect sheets can only be laid in one direction this is due to the gutter detail at the bottom of the sheet.
In other words if the height of the roof drops by 2 inches for every 12 inches in length you will need to use sealant to strengthen the overlap barrier.
