The first point to be made is, when re-covering a roof, all old felt must be removed and the surface on which it was laid must be carefully checked and if necessary, made good. If roofing felt has been defective for some time, there is every chance that constant wetting may have caused damage, and rot may be present or developing. Any damaged timber or boarding must be replaced. For further information, please check out our Good Ideas Leaflet 64 http://www.wickes.co.uk/content/ebiz/wickes/resources/images/gil/64.pdf
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