Cure It GRP, Руководство по установке

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Troubleshooting guide
Problems that occur after the roof has been laid
6) Board swelling (‘tile’ outline on the roof)
Description of problem - This will cause a ‘tile’ effect to appear on the roof as the outlines of the boards appear as ridges on the roofs surface.
The roof is unlikely to leak, but in very bad cases, some cracking may occur at the joints.
Possible cause Remedial action
• This is caused by moisture uptake in the boards. It may be due to • The roof must be cleaned and all of the ridges ground down.
excessive condensation, but is more likely to be a result of some • New expansion joints must be fitted to the roof using E280 trims
porosity in the laminate, allowing water to seep into the boards. and the entire roof surface must be re-laminated.
• The problem is made worse by poor board fixing, allowing the • In bad cases, it may be necessary to grind down the ridges and
boards to move and rise up off the roof timbers. fix new boards over the existing roof and re-laminate, ensuring
• Insufficient expansion gaps have been left between the boards if adequate provision for board expansion with expansion joints
over 100m
2
. on larger roofs and ability to fix into joists by minimum 40mm.
• May cause ponding (see above.)
7) Tacky topcoat
Description of problem - Topcoat has suitable hardener and has been adequately mixed but is still tacky. This problem usually manifests
itself in very hot conditions.
Possible cause Remedial action
• This is usually caused by application of the top coat in hot, sunny • Clean down with acetone and re-apply in cooler conditions.
conditions, so that the waxy surface layer cannot properly form. • Tacky topcoat usually occurs at approximately 5 o C surface
temperature and this is usually caused by very hot conditions
and direct sunlight.
8) Colour fade of topcoat
Description of problem - This can take several years to appear and the problem may be worse if the topcoat was tacky when first laid.
Possible cause Remedial action
• This is caused by erosion of the topcoat and is more likely to occur • It may be possible to clean down, abrade and re-topcoat the roof,
with darker colours. but it is difficult to guarantee that no topcoat delamination will
• The effect of the colour returning when the surface is wet with rain occur thereafter.
is often reported. • The only way to guarantee the longevity of the colour is to re-skin
the roof with another laminate and re-topcoat.
• This is also a method for refurbishing old, damaged or well-worn
roofs that may have been subjected to heavy foot traffic.
8) Pinholing
Description of problem - Pinholes appear on roof causing roof to leak in most cases.
Possible cause Remedial action
• Too little resin being used during the laminating stage resulting • During the consolidation of the laminate, extra care should be taken
in pinholes where the laminate has not been saturated with resin. to identify any areas with small pinholes. If the laminate is not yet
• Improper consolidation of the laminate resulting in small holes in cured, more resin should be added and the area should be
the laminate where the resin has not been treated. properly consolidated.
• If the area has cured, a section of new reinforcement mat should
be torn to be used as a patch. Resin should be applied over the
affected area and the patch should be laminated ensuring it is
properly consolidated.
• Do not use topcoat to attempt to cover pinholed areas. This will
not work!