Hi All

Apologies again for the delay in posting. It's been very busy, both personally and in the business, which has meant we have strugggled to keep up with our online presence as much as we like.

An area of our business which is constantly expanding is our Fibreglass and Resin products.

We get many questions from people who are doing anything from making a pond to re-surfacing their roof. Fibreglass is a useful and adaptable material, and if used correctly, will result in a strong, waterproof, professional end result.

We purchase our products direct from the manufacturer, in very large quantities, which is why we are best placed to offer low prices and high quality goods. 

We offer Lloyds Approved resin and topcoat - this is important. Lloyds Approved means that it is the correct product to use in boat building and repairs. We supply this resin as standard, which means if you are re-surfacing your roof, or lining a pond, you are getting the best quality products.

CFS are a large UK manufacturer / supplier of all things fibreglass and resin. We give them full credit for the information and guidelines below. We are aware of some suppliers out there, particularly in the paint industry, who copy and paste other peoples work and pass it off as their own. 

We do not do this. We could write a full guide on fibreglass and resin, but with such experience and professionalism that CFS show, we fully bow to their experience. Below is an excerpt from the fibreglass guide which we think you will find useful.......

Fibreglass Flat Roofing 

A properly laid fibreglass roof also known as GRP Roofing, will last for at least 30 years with no measurable deterioration. The roof must be laid onto a dry deck in dry conditions at a temperature not below 5°C. The resins and top coats should be suitable for use in GRP Roofing. This guide relates only to the application of the GRP laminate and top coat. Typically two men can strip, re-deck, laminate and top coat a roof of about 20 square metres in one day. Always try to plan starting the roof when a settled period of weather is forecast.


The laminating must be planned depending on the air temperature. Long runs may be attempted in cooler conditions while short runs must be used in hotter conditions. Remember that the resin will always cure faster in hotter conditions and an allowance must be made for this when deciding how much glass to lay in one mix. (The Glass : Resin ratio should be 1:2.5). Before the laminate is applied the glass must be pre-cut to the desired length., shorter lengths in hotter conditions. The laminate need not be laid to falls, i.e. it does not matter in which direction the joints are lapped. Clear all unnecessary items off the roof and mix sufficient resin and catalyst to complete the first "run". Wet out the first area to be done and roll out the glass. Apply the remainder of the resin to the glass, allow to wet out for a few minutes, then consolidate the glass with the consolidation roller ensuring that no dry patches of glass remain and that no air is trapped in the laminate.

Continue with the next "run" of glass overlapping the first by 5Omm. Do not step on the wet glass and resin. Continue this until the roof has been completely covered and the laminate has been well consolidated.

Top Coating:

 The laminated roof must be top coated as soon as possible - Try not to leave the laminate overnight. Test the laminate for cure by using slight finger pressure. The laminate is about half cured when it is impossible to move the glass fibres within the resin matrix. At this point it will withstand light foot traffic so that you may stand on the laminate to complete the top coating. If you are working alone, decant topcoat into buckets of no more than 3kg (enough to cover about 6m2). Catalyse and use one mix at a time, applying with a roller, keeping a wet edge, immediately catalyse the next bucket of topcoat and continue from where you stopped. Decant a small amount to finish the edges and all details work.

 Ensure that the top coat is even and not more than half a mm thick. If the top coat is applied too generously, there is a danger that it will crack. The GRP Roof is then complete and will take several days to fully cure. It will not deteriorate and maybe cleaned occasionally with soap and warm water. DO NOT USE BLEACH or any strong alkali on the roof. The roof will withstand foot traffic and may have planters or tiles or other decorative finishes applied to it with no detrimental effects. The edge trims may be painted if required.

Catalyst additions: 

 1) Never use less than 1% even in summer. Just mix less at a time.

 2) Never use more than 4% - the cure time will not reduce with more catalyst beyond 4%.

 3) Never underestimate the effect of temperature. Resins will not cure at or below freezing and will always cure much faster in direct sunlight.

 4) Remarks - when Top Coating late in the day - add more catalyst to allow for the lack of sunlight.

 5) You can buy catalysts of different strengths, to partially compensate for winter and summer conditions.

 6) Remember any catalysed resin left in the bucket will exotherm. Heat is generated as it cures and it should be left well away from other stored materials. Water may be poured over the resin layer in order to suppress heat gain.


 You may encounter some problems when laying the GRP Roof or after its completion. If these instructions have not been followed.

1) Delamination of the laminate from the boards: Moisture in the deck when laminating.

2) Flaking and Cracking of the top coat: Top coating onto a wet laminate or applying the top coat too thickly.

3) Resin cures too fast: Conditions are too hot to lay resin or addition of too much catalyst.

 4) Top coat cures too fast: See No.3.

 5) Resin cures too slowly or not at all: No catalyst addition or temperature too low. The cure will stop and temperature drops to freezing.

6) Patch or Streaky cure of resin or top coat: Insufficient catalyst and inadequate mixing.

7) Resin does not cure and appears milky white: Water contamination.

8) Excessive fibre pattern: Too little resin and insufficient consolidation.



It is provocative to say the glass fibre and polyester resin (glass reinforced plastic = GRP) is as easy to apply as wall paper. Given the correct materials and the proper preparation and advice - it is no more difficult. Should you have the pond professionally built and GRP lined ensure that the firm carrying out the work has wide experience of pond construction as opposed to general glass fibre work. At the very least they must be fully aware of the toxic effects of solvents and chemicals on fish and therefore the absolute necessity of proper curing (hardening) of the laminate and topcoat system.

 Type of structure:

It is important that the structure, which is to be lined with GRP, is capable of withstanding the soil and water pressure in its own right. Whilst the glass fibre will naturally add to the strength and rigidity it is not, in this case, being used for this purpose. Normally the pool is constructed from brick, lightweight block or concrete block. With the exception of brick built ponds, it is necessary for a cement render to be applied and for sufficient time to be allowed for it to dry. Bear in mind that a half inch cement render should be kept damp for 3 days. A further 10 days should be allowed, at reasonable temperatures and dry conditions, before it will be possible to apply the G4 primer coat.

 Polyester Resin:

 There are many formulations of polyester resin but all contain around 35% styrene monomer which can, unless the laminate is properly cured or hardened, have a toxic effect on fish. However the fact that there are many GRP lined ponds, including the ready made ones, means that providing the correct materials and methods are followed a GRP lining is non toxic to fish. There are two types of polyester resin that are used. One is a general purpose - pre-accelerated resin with a slight thixotropy to enable it to "hold up" on vertical surfaces and the other a highly thixotropic resin - referred to as a Gelcoat - both of which, as stated earlier, contain styrene monomer. Most general purpose resins contain some amine - 0.1 to 0.2% (by weight) but this is required for the proper curing of the resin, although it is considered toxic to fish.

The Method: 

At the beginning the process was likened to hanging wall paper. The difference between the two systems is that with wall paper you paste it first then hang it whereas with glass fibre you "impregnate" it after it has been laid into position. However as with wallpapering, material preparation is of paramount importance. The glass fibre should be cut to the required lengths and the edges to be overlapped frayed out (see later section). Initially the resin should be measured out and the catalyst addition decided and tools should be to hand. It sounds simple and it is but by carrying out these preparations you will find that the laminating work is made easier because you are able to pick up the correct length and shape of glass fibre rather than cut and tear halfway through the operation. If you have not worked with GRP before carry out a trial, on an old piece of board, so as to get some practical experience. It is suggested that the walls are coated first starting at a corner. Therefore cut the glass fibre mat to the correct length allowing for say a 6" to 8" overlap at both the top and bottom of the wall. When you are designing or building a pond do remember that it is difficult to laminate into or around right angled corners and therefore both the internal and external corners, where possible, should be radiused. The glass fibre - two or three layers - must be applied "wet on wet". This means that while the first layer of glass fibre can be the full width 36 inches (92.5cm) the second should be cut to 30 inches to allow for an overlap for the next section when laid. If three layers are being applied then of course the third layer should be cut to 24 inches again to allow for an overlap. When cutting glass fibre where there are to be joints always fray out the edges since when overlapped the frayed edges will allow an almost undetectable joint to be made. Glass fibre can be cut with a Stanley knife, scissors or with a little practice torn which "builds in" the frayed edges. If cut, tease or tear the edge to fray it.

Applying the Laminate: 

With the G4 at the finger tacky stage mix a quantity of resin with the catalyst, mixing it in thoroughly. (See section on catalyst addition) Until you have experience do not mix up too much resin at a time certainly no more than 2kgs, enough for between 1 and 1.5% sq/m of glass fibre. For large flat areas it is quicker and easier to apply the resin using a medium pile roller. Roll on a coat of catalysed resin to the G4 and then lay on the first section of glass fibre, apply more resin to "wet out" (saturate) the glass fibre. As the binder holding the glass fibre dissolves it will become translucent. Then apply the next layer (30 inches wide in this case) and again apply more resin. Once the glass fibre has been "wetted out", it is necessary to consolidate the two layers of glass fibre and this is done using a metal roller. The roller can either be of the aluminium ridged variety or a metal washer roller but used vigorously it not only forces the two layers of glass fibre together but it removes any trapped air, this appears in a laminate as a whitish blister, and care must be taken to ensure that this is done. If a third layer is being applied the procedure is the same although the width of the glass fibre is only 24 inches to allow for an overlap. Having completed this section move on to the next and with the overlap built in full widths can be used. Unless the corners are radiused do not attempt to take the glass around the corner since it is difficult to "persuade" glass fibre to lie into right angled bends, start again with a built in overlap. Since there will be a butt joint at the corner it is then recommended that a strip of fibre glass some 8 inches is cut with the edges frayed out and then applied as a tape would into the corner. You will find that this is easier since the glass can be bent into shape. Once the glass fibre has been "wetted out" it is easier to "work" into corners and around more complicated and compound shapes. For this purpose a brush is used with a stippling action and if required the glass fibre can be pre-wetted out on a flat board before being stippled into position. The base of the pond is usually done last.


As you can see from the snapshot of information above, using fibreglass is a process that needs to be followed and planned meticulously. However, it is without doubt, well within the capability of anyone with basic DIY skills. And remember, we are here to help. 

I was talking to a customer recently who was filling me in on another paint supplier he had dealings with. There were 2 main complaints: 1) Their prices were ridiculously inflated and, 2) They always did the "hard sell". Yes, we understand that all businesses are out to make money, but we do not believe in hiking up the prices of goods just because we can. We believe that all products should be made accessible to everyone, at reasonable prices based upon availability and specification. 

Our main work ethic also answers his second point of concern - we do not and will not subject our customers to a hard sell. We will always offer advice, unbiased, whether that results in a sale or not. Of course, if we have the products to satisfy the customers requirements, we will bring attention to these. However, if we don't, we will always honestly say so. 

That's why we are proud to proactively advertise that the above instructions are from CFS, our supplier and one of the UK's leading providers of fibreglass and associated products.

If we can be of anymore help - you know where we are


Until next time




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