Home Troubleshooting Guide

Troubleshooting

Failure of resin to cure/harden
Resin cures too fast
It begins to rain while laminating/topcoating
Water contamination (white staining of laminate)
Streaky laminate/topcoat
Failure of topcoat to cure
Entrapment of debris in laminate
Spillages
Delamination of the laminate from the boards
Delamination of topcoat
Cracking of the topcoat
Cracking of laminate
Ponding/standing water
Board swelling ('tile' outline on the roof)
Tacky topcoat
Colour fade of topcoat

Failure of resin to cure/harden

Description of problem
Laminate is still wet and resin is uncured with no other symptoms.
Possible cause Remedial action

Resin may have been inadequately mixed.

Unsuitable catalyst may have been used (e.g. LPT or summer catalyst used in winter).

Not enough catalyst may have been used for the temperature.

Catalyse another batch of resin, ensuring that you use the correct catalyst. Always add extra catalyst (doubling up if necessary) and roll vigorously into the resin.

Larger laminates or laminates that have been left for a long time or contaminated by dirt, debris or water etc. will need replacing completely.

Always check the ambient temperature before mixing batches of resin and consult the catalyst chart for guidance if unsure.

Resin cures too fast

Description of problem
Resin cures before it can be properly applied and consolidated into the CSM.
Possible cause Remedial action

Resin may have been inadequately mixed. Unsuitable catalyst may have been used (e.g. LPT or summer catalyst used in winter).

Not enough catalyst may have been used for the temperature.

If the ambient temperature is very hot or there is a lot of direct sunlight, use LPT (Long Process Time) catalyst.

Reduce the size of the batches mixed.

Always ensure that you are laying the shortest possible runs across a roof to give you adequate time to properly consolidate the laminate.

It begins to rain while laminating/topcoating

Description of problem
Roof has not yet cured and it begins to rain.
Possible cause Remedial action

N/A

STOP! Cover the roof with a non-woven polyethylene sheet and try to ensure that non of the laminate gets any moisture onto it.

Always ensure that you check the local weather forecast before you start a roof.

Always have enough polyethylene sheets with you to cover the roof. Resin contaminated with water will not cure and require a re-skin (see below).

Water contamination (white staining of laminate)

Description of problem
Water contaminated resin usually appears as a white staining or milkyness. The resin will not fully cure.
Possible cause Remedial action

Resin has been contaminated by water.

Any white areas should be laminated over fully with a 450g/m2 laminate.

Streaky laminate/topcoat

Description of problem
Laminate has partially cured, but has streaks of wet resin or lighter/darker colours running through it.
Possible cause Remedial action

Resin may have been inadequately mixed.

Pigment may not have been mixed in thoroughly.

Always ensure that topcoat is applied thinly (0.5mm). This makes it possible to reapply another layer of either properly catalysed or throughly mixed, pigmented topcoat. If usingpigment or catalyst, add more to the second coat.

Failure of topcoat to cure

Description of problem
Topcoat is still wet and has not cured.
Possible cause Remedial action

Topcoat has been used with unsuitable catalyst (i.e. Summer catalyst in winter).

Topcoat has not been sufficiently mixed or not enough catalyst has been mixed in.

Topcoat might be contaminated by water.

After water has evoparate apply another very thin layer of topcoat, ensuring that it is vigiriusly and thoroughly rolled in to the uncured layer.

Always add more catalyst to the second batch, up to double if necessary.

Entrapment of debris in laminate

Description of problem
Debris entrapped in the laminate, possibly poking through the laminate, holes in laminate.
Possible cause Remedial action

N/A

This is usually seen while consolidating. The debris needs to be removed and patched over. This can be done while the laminate is still wet and then patched up with a new section of laminate.

When the laminate has cured, the surface can be lightly rubbed with a coarse sand-paper. This will highlight any imperfections. The affected area must then be pactched with a new laminate.

Spillages

Description of problem
Spillage/resin spray.
Possible cause Remedial action

N/A

Resins stick by mechanical adhesion; they soak into a surface and cure. It is essential to clean the resin off the surface before it cures.

The solvent for uncured resin is acetone. This can be used to remove resin from most surfaces including clothing (WARNING: acetone is extremely flammable).

If used to clean paintwork or coloured fabrics it may discolour or remove paint or dye from the surface.
Resins will generally not adhere to anything that has a shiny surface.

If resin has cured onto a surface such as glass, metal or paintwork, it may be flicked off using a sharp edge or by vigorously rubbing with a coarse cloth. The cleaned surface maythen be buffed with wax polish or a cutting compound.

With larger spillages (e.g. driveways or walls), a hot pressure washer is the best choice, but high pressures will be required and strong detergents are usually necessary.

Preventative measures are essential to avoid spillages.

Always mask off adjacent areas where fine spray droplets, caused by the consolidator roller, may fall. Polythene sheeting is the best material for masking.

Delamination of the laminate from the boards.

Description of problem
This will not cause the roof to leak.
Possible cause Remedial action

This is caused by poor adhesion of the laminate to the boards and is more likely to happen with plywood rather than OSB.

The laminate can be completely removed and reapplied after priming the boards with G4 (to ensure no further delamination occurs).

Delamination of topcoat

Description of problem
This will not cause the roof to leak.
Possible cause Remedial action

Application of the topcoat to a contaminated surface (usually wet).


Application of the topcoat to a hot laminate may also cause this to happen.

Whenever the adhesion of the topcoat is poor, some topcoat delamination may occur.

The topcoat cannot just be reapplied on top of existing topcoat.

Generally, the best solution is to clean and abrade the surface, removing all of the flaking top coat, then re-laminate the entire roof surface and reapply the top coat.

Cracking of the topcoat

Description of problem
Cracks may appear as fine lines on the substrate. This will not cause the roof to leak.
Possible cause Remedial action

This is usually caused by the topcoat being applied too thickly, topcoat should never be applied thicker then 0.5mm.

The only solution is to relaminate over the cracked area after careful surface preparation.

Cracking of laminate

Description of problem
Could cause the roof to fail if cracking is severe enough.
Possible cause Remedial action

The roof is over 50m2 and an expansion joint has not been incorporated into the roof.

Grind down and laminate over the crack with two layers of 450g/m2 CSM.

It may be necessary to cut out a section and laminate in an expansion joint at 50m2 intervals.

Always check the board fixings, these may need to be re-fixed if they have been pulled away from the joists.

Ponding/standing water

Description of problem
A common problem and one which will not affect the performance of the roof but can be unsightly when a roof is overlooked, or, worse still, if it occurs on a balcony.
Possible cause Remedial action

The roof has been installed with an inadequate fall.

The decking has not been rebated where A-trims have been attached, causing a lip which holds water back.

May cause ponding (see above).

A filled resin concrete can be applied to the area where the water ponds. This must then be laminated over to ensure that there is no surface cracking.

While this will displace the water, the best solution is to ensure that the original quotation confirms that the roof may be subject to ponding, and unless specified, it is difficult to guarantee that this will not occur.

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 excessive condensation, but is more likely to be a result of some porosity in the laminate, allowing water to seep into the boards.

The problem is made worse by poor board fixing, allowing the boards to move and rise up off the roof timbers.

Insufficient expansion gaps have been left between the boards if over 50m2.

May cause ponding (see above).

The roof must be cleaned and all of the ridges ground down.

New expansion joints must be fitted to the roof using G180 trims and the entire roof surface must be relaminated.

In very bad cases, it may be necessary to fix new boards over the existing roof and relaminate, ensuring adequate provision for board expansion with expansion joints on larger roofs.

Tacky topcoat

Description of problem
Topcoat has suitable catalyst 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 conditions, so that the waxy surface layer cannot properly form.

It may be possible to clean down, abrade and re-topcoat the roof. Clean down with acetone and re-apply in cooler conditions.

Tacky topcoat usually occurs at approximately 55oC and this is usually caused by very hot conditions and direct sunlight.

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 with darker colours.

The effect of the colour returning when the surface is wet with rain is often reported.

It may be possible to clean down, abrade and re-topcoat the roof, but it is difficult to guarantee that no topcoat delamination will occur thereafter. It is possible to use a PU varnish to restore the colour, but this may have to be reapplied after 2-3 years.

The only way to guarantee the longevity of the colour is to re-skin the roof with another laminate.

This is also a method for refurbishing old, damaged or well-worn roofs that may have been subjected to heavy foot traffic.

The roof needs to be completely cleaned down and wiped with acetone. G4 primer should then be applied on top of the laminate and the topcoat can be applied on top of this.