Roofs
When our Valleys terraces were originally built, the roofscape would have been quite different to what we see today. Most roofs were covered in North Wales slate, creating a unified look to the street, and every house would have had a chimney stack, adding a strong rhythm that made the Valleys terrace special.
Natural slate
Welsh slate is universally regarded as being among the best and longest lasting in the world. However, the iron nails commonly used for fixing the slate were less durable with the result that, a hundred years or more after they were built, most roofs have been resurfaced, with often sound slate abandoned in favour of inferior artificial slate or concrete tile.
A good ‘hat’ is important to any house, and replacing your roof using new (or reclaimed) natural slate, rather than the more commonly used artificial slate or concrete tile should be given careful consideration.
Most of the ‘later’ Valleys house types would have been originally roofed using 24” by 12” natural slates, with angular (rather than half-round) blue-black ridge tiles. It’s very important to use the correct preservative treated battens, breathable underlay and of course, nails (preferably copper), if the problems of our original roofs aren’t to be repeated.
Did you know?
Modern concrete tiles can weigh up to twice as much as the original thin slates that were on our Valleys houses. Building Regulations Approval is therefore required to change from slate to concrete tile.
Imported natural slates that match the grey or heather blue colour of the original Welsh slate are a more cost-effective solution but it is important to source the slates from a reputable quarry to avoid the long term problem of slate weathering.
Slates from different sources should not be used on any one slope as this can lead in time to a patchwork effect. Where possible, roof vents that protrude above the slates should be avoided and ventilation of the roof void provided by using a breathable construction.
Interlocking concrete tiles give a much ‘coarser’ appearance to the roof than natural slates and can overload a roof structure that has been designed for lighter, natural slates.
Similarly, fibre cement slates or any other man-made slate tend to give a ‘smooth’, uniform appearance and lack the character of natural slates.
Conservation type rooflight
Rooflights and dormers
Rooflights and dormers would not have been a common feature on Valleys house roofs when they were originally built. Where loft spaces are converted and rooflights or dormers are a necessity, they should only be situated on rear elevations as they break up the plane of the continuous roof slope on the street side.
Consideration should be given to using modern, double glazed versions of early cast-iron rooflights (to the correct proportion and size, complete with a vertical glazing bar) to retain the character of the roof as much as possible.
