Slate Roof Headlap

Figure 4 shows a roof that was installed with negative headlap.

Slate roof headlap. Most stock slates will be pre holed at 75 90 or 100mm allowing you the versatility of different pitches commonly 25 degrees in moderate exposure zones and 30 degrees in severe. Such a roof is like a sieve. Minimum headlap for fixing slates with nails or hooks the installation of a slate roof involves a number of aspects that must be considered in the design process. Headlap exposure and offset.

Laying slate with appropriate headlap and offset helps to accommodate wind driven rain and the lateral movement of water below the slate shingles to prevent infiltration through the nail holes and side joints. Holing gauge batten gauge headlap 10mm. 3 before you start do your homework. Read about how to install starter courses take a look at common contractor errors watch some video clips read about drip edges and cant strips if necessary look at some of the nuances that may be pertinent to your installation such as cleats on aprons cleats on.

Roofs shallower than 4 12 should not be made of slate according to traditional roofing. If your property s roof is in the green moderate part of the uk but you know of prevailing bad winds or weather you may wish to use the other chart instead. These are all words that should send a chill up the spine of any good slater. Minimum recommended headlap mm unit 15 16 airfield approach business park flookburgh grange over sands cumbria la11 7ng england tel.

A slate roof with inadequate headlap. Understand headlap read about the common mistakes people make when installing slate roofs. The most commonly used slate size in southern england is 500x250mm and 400x250mm in scotland and the north of england. The minimum roof pitch for natural slates is 20 degrees bs 5534 2014 page 45 depending on size of slate see table above bs 5534 2014 page 45 table 9.

Once you have chosen pitch and headlap you ll be able to determine the number of slates you ll need per m 2 using our coverage tables. Better to err on the side of caution and install a roof with extra headlap than skimp and risk having to remove the entire roof and start over. If your roof is shallower between 4 12 and 8 12 the slates should have a headlap of at least four inches. Notes from bs 5534 2014.

Minimum slate headlap moderate weather this table of slate overlaps and roof angles shows common sizes of roofing slate and the recommended slope for the corresponding slate size.