search.noResults

search.searching

note.createNoteMessage

search.noResults

search.searching

orderForm.title

orderForm.productCode
orderForm.description
orderForm.quantity
orderForm.itemPrice
orderForm.price
orderForm.totalPrice
orderForm.deliveryDetails.billingAddress
orderForm.deliveryDetails.deliveryAddress
orderForm.noItems
Roofing Give-and-take


Andy Fell of Hambleside Danelaw summarises the pros and cons of different flat and low-pitched roofing membranes


H


ousing maintenance is a demanding task, with cost, performance, lifespan, ease of installation and maintenance being the main governing factors. ‘Traditional’ roofing systems are still considered to


be valid for certain applications, but there are alternative products that should always be appraised for their merits.


BITUMINOUS A good, robust product compatible with many other systems, with extremely good flexibility and resistance to rupture. Naked flame use however makes this a risky choice on combustible substrates, and the heavy environmental cost of sourcing and manufacture weigh against it.


PVC Aesthetically pleasing, speedy to apply, easy to make a roof look decorative using standing seams applied to the surface. But, as well as being difficult to repair after long-term weathering, the potential for damage by following trades makes the specification of PVC waterproofing one to give serious consideration to if a roof is going to be trafficked.


TPO Fairly robust, aesthetically pleasing, speedy to apply, and easy to make a roof look decorative using standing seams applied to the surface. TPO however is incompatible with many other membranes, especially bitumen, and can be difficult to repair after weathering. Like PVC, the potential for damage by following trades makes the specification of TPO waterproofing one which requires careful consideration.


The suitability of alternative waterproofing systems for refurbishment work does offer a wide choice


LIQUIDS Polyurethane and PMMA (Poly Methyl Methacrylate) liquid systems can be ideal for awkward detailing with multiple roof penetrations. Quick curing acrylics such as PMMA are ideal for trafficked surfaces, but for refurbishment, these systems rely more heavily on the quality of preparation and condition of the underlying layers and substrate to be successful, so the relatively high cost of the product, added to extensive preparation can lead to an expensive system; the cost of which exceeds many other solutions.


EPDM This can be a very hard wearing and robust waterproofing material which is usually adhered to the roof or laid loose and ballasted. However, failed EPDM roofs generally happen because detailing is more difficult to achieve, and the adhesive bonding upstand membrane can disengage from the substrate, causing flashings to fall away. Additional fixing at edge detailing is generally required, which usually means fixing through the completed membrane.


www.housingmmonline.co.uk | HMM March 2018 | 45


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52