Roofers Dublin

Tile/Slate your roof.

Roof tiles are typically fired clay or coloured concrete, and come in a variety of shapes and sizes. Here we deal with the key points of tiling/slating any roof, which is setting it up. If you want to know how to replace all types of roof tile, including hanging tiles, read more below…

How many roof tiles you need

The best way for domestic properties has always been simple, make an educated guess. By that I mean write down the Width and Height of each individual face of the roof on a piece of paper. Then when you add them up you are going to be left with a metreage or square footage figure. You can also measure the width from ground level, I find it’s quite easy to work in metres from my minds eye, but then again I’ve done a lot of it. Alternatively get a nice strong tape measure, get up some ladders and measure it.

Now you have a square metre or square foot figure, ring up your local hardware supplies merchant and they will work out how many tiles you require for your roof. Usually the hardware employees are very good to tell you what and how much you want.

Roofing laths get the battens

Roof lath or roofing battens, two different names for the same thing. Strips of timber often treated with a wood preservatives. These are nailed into the roofing joists or roof trusses beneath and provide support for the roof tiles or slates, fixings can then be made into the roofing lath or batten if required.

The most common sizes are…

Commonly called tile or slating laths or battens.

• 25mm x 38mm (1″ x 1^{1/₂ “}) Commonly called tiling lath or tiling batten, often used on rafter spans of 450mm or less.
• 25 or 30mm x 50mm (1 – 1^1/4  ” x 2″) Mostly used in modern tiled roofs, often used on rafter spans of 600mm or less.

Roofing battens – Common sizes of tile lath, slate lath or tile batten are 2″ x 1″.

How to space roof tiles and space roof battens or laths

The most common mistake made is that the tiling takes place at the bottom of the roof from the scaffold at gutter height, no thought is then given to whether the tiles will be correctly spaced by the time you get to the top of the roof. When laying roof tiles it’s important just to spend a little time planning tile spacings first.

Once the old roof has been stripped all the way to the bottom, the rafters or roof trusses will be fully exposed. Make sure the rafters are clear of any stray nails or splinters, tha they are ready to take the felt or breathable roofing membrane and not rip or puncture it. One full width of roofing felt will been fitted.

How to lay roofing felt or roofing membrane

Start at the start on one edge of the roof and fix with two or three nails then roll out the felt keeping it taught but with a very slight hint of sag, this will ensure any water that does end up on the felt will run between the rafters and end up in the gutter. Make sure about 30 to 40mm of felt hangs over the fascia and into the gutter. On a adverage construction, if there is a cavity wall, make sure you bridge the gap over any cavity with the felt.

The second level of defense the felt.

• Joining the felt – Overlap any vertical joins by 100mm about 4 inches onto a rafter or truss
• Overlapping felt – When laying the next layer above the pervious overlap, make sure the cover is about 4 – 6inches
• On a Hip –  Make sure the felt or membranes overlap goes around onto the next face of the roof about 4 – 6inches
• On an upstand – Where the roof joins or abuts a wall turn the felt or membrane up the face of the wall for 4 inches
• On the verge – Cut the felt or membrane at the outside edge of the last joist
• At the ridge board (the point of the roof) – Overlap 150mm (6″) over the top of the roof onto the other elevation.