KoverTek TekShield GRP Roof Kits utilise KoverTek’s TekShield Roofing Resin Basecoat and either TekShield Standard Roofing Topcoat or TekShield Flexi Fire Rated Topcoat to create an easy to use kit with everything you need to complete a roof. Available in two versions; ‘Standard’ and ‘Fire Rated’ both offering 20 or 25 year material guarantees in pack sizes up to 32m² per kit.

Please note: These kits do not include KoverTek GRP Roofing Trims which need to be purchased separately.

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• Features & Benefits
• How to Use
• Preparation
• Installation of Trims and Tape
• Basecoat Application
• Topcoat Application
• System Notes
• Disclaimer

Features & Benefits

KoverTek TekShield Roofing Resin Basecoat

• High performance virgin resin
• LSE (Low Styrene Emission) system - prevents excessive smell when working
• Colour change mechanism to indicate cure
• Quick wet out of Chopped Strand Mat
• Hand & Spray lay
• Low drainage
• Medium cure rate that allows for all round use

KoverTek TekShield Standard GRP Roofing Topcoat

• Pre-accelerated and thixotropic
• Good weathering resistance
• Flexible
• Brush or roller applications
• Very good coverage and opacity to ensure a streak-free finish
• Excellent bonding
• Good hydrolysis resistance

KoverTek TekShield Flexi Fire Rated Topcoat

• Fire Rated
• Flexible topcoat to prevent cracking and movement noises
• Superior weather and crack resistance
• LSE (Low Styrene Emission system) – Reduced emissions and smell
• Brush or Roller application
• Class beating Fire rating EN 1187 test 4 – BROOF(t4) tested as a flat roof laid onto OSB3*

* Please refer to full certificate if required.

• Click HERE to view standard kit contents
• Click HERE to view fire rated kit contents
• Download your Guarantee Form to complete – Retain copies of materials purchased and dates of installation, these will be required to obtain the material guarantee and must be produced in the event of a claim.
  • 20Yr Guarantee
  • 25Yr Guarantee
• Download your Coverage Guide

How to Use

• Suitable substrates for KoverTek TekShield GRP Roof Kits;

Designed to be used on OSB3 board or similar wooden substrates. All substrates must be clean and dry, do not lay on wet or damp surfaces as this will adversely affect the cure.

Always carry out a test patch prior to large scale application.

Recommended working temperatures +10°C - + 25°C.

Approximate working time with catalysed KoverTek TekShield Roofing Resin Basecoat and Standard GRP Roofing Topcoat will be 18-45 minutes depending on temperature. Care must be taken when working at higher or lower temperatures.

Preparation

Make sure that before starting any GRP roof work that the outside temperature is above 7.5°C and it is unlikely to rain within 2 hours of finishing the roof in order to allow the resins to properly catalyse and cure. KoverTek TekShield Roofing Resin Basecoat and Topcoats will not cure sufficiently in very cold and / or wet conditions and the roof could fail if you ignore this. Always store KoverTek TekShield Roofing Resin Basecoat and Topcoats indoors in original, unopened, undamaged containers in a dry place out of direct sunlight and bring up to 15°C prior to use.

Strip the old roof covering from the timber substrate. If the existing timber is rotten, this must be replaced with OSB3 18mm “sterling boards”. These are tongue and grooved for easy installation and typically measure 2.4m x 0.6m.

Place the OSB3 Boards at an angle of 90° to the existing roof beams and screw in place. As with any wooden floor or deck, stagger the joints in such a way to create a strong structure. Start placing the boards from the furthest edge from the drip trim. If a board is laid along a wall, an expansion gap of 25mm should be left. Timber absorbs moisture so before you start application of TekShield Roofing Resin Basecoat ensure that the deck boards are totally dry to avoid future movement that may cause joint failures.

If working conditions allow, incorporate a drainage channel in the roof surface to allow standing water to escape from the roof. If this is not possible you should add some triangulated extensions to the roof joists before adding the OSB3 deck.

Always ensure that there are no gaps between the OSB3 boards once in place and that a 25mm expansion gap is left where there are adjoining walls. Trims and upstands will be placed here to create the required watertight seal. It is particularly important to prepare well to ensure the roof is constructed to last and be problem-free. A screw gun is recommended to fix the deck to the joists and you must ensure screws are of sufficient length to give enough penetration to the joists below. This ensures the structural integrity of the finished roof.

Installation of Trims and Tape

The roof trims can now be attached and the up-stands secured to any adjoining walls ready to take the GRP flashings. All the board joints and all the trims must be "taped" (with the woven tape included in the kits) to the roof to prevent stress cracking at the joints. This is done by applying the 3” wide woven tape to each joint and to all the trim edges. The tape must be well consolidated with TekShield Roofing Resin Basecoat. The procedure for taping is the same, on a smaller scale as that used for the main laminate (application of TekShield Roofing Resin Basecoat and Chopped Strand Mat (CSM)).

Decant about 1 kg of TekShield Roofing Resin Basecoat into a small bucket and mix with catalyst (the correct amount of catalyst – all items included in the kit). Apply to the board edges and to the trim edges with either a 3” brush or small roller (included in kit). Roll-out the pre-cut woven tape over the TekShield Roofing Resin Basecoat and apply a further amount of TekShield Roofing Resin Basecoat to the woven tape, consolidating with a small metal consolidation roller (included in kit).

All the detail work may also be completed at this stage. Tape all drain outfalls, channels, pipes and roof fittings using this procedure. You may find a brush easier to use than a roller on complex shapes. Nail or staple the trims to the roof deck. Flat flashing (F300) and angle fillets (D260) need to be bonded using a PU/MSP adhesive or Fix-All Flexi. Non-structural adhesives such as silicone or mastic must not be used as the bond strength will not be sufficient to prevent leaks.

Basecoat Application

The main application of TekShield Roofing Resin Basecoat and Chopped Strand Mat (also referred to as ‘laminate’) may be applied before or after the woven tape application has cured. TekShield Roofing Resin Basecoat will always cure faster in hotter conditions and an allowance must be made for this when deciding how much Chopped Strand Mat to lay in one mix. (The Chopped Strand Mat : TekShield Roofing Resin Basecoat ratio should be 1:2.5). Pre-cut the Chopped Strand Mat to the desired length. It does not matter in which direction the joints are lapped.

Mix sufficient TekShield Roofing Resin Basecoat and catalyst to complete the first “run”. The TekShield Roofing Resin Basecoat needs to be applied quickly after adding catalyst as the curing process will have started and you have limited working time. Apply TekShield Roofing Resin Basecoat to the 1st area to be covered and roll out the Chopped Strand Mat on top. Apply the remainder of the TekShield Roofing Resin Basecoat to the Chopped Strand Mat, allow to wet out for a few minutes, then consolidate the Chopped Strand Mat with a metal paddle roller ensuring that no dry patches of mat remain and that no air is trapped in the TekShield Roofing Resin Basecoat.

Continue with the next “run” of Chopped Strand Mat overlapping the first by 50mm. Do not step on the wet Chopped Strand Mat and TekShield Roofing Resin Basecoat. Continue this until the roof has been completely covered and the system is well consolidated.

TekShield Roofing Resin Basecoat needs to be left to cure for between 1 and 4 hours depending on application conditions. Test the system for cure by using slight finger pressure. The system 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 system to complete the top coating. Try not to leave the system overnight.

Topcoat Application

Before KoverTek Standard GRP Roofing Topcoat can be applied, lightly sand the TekShield Roofing Resin Basecoat and Chopped Strand Mat surface before applying the topcoat. Add the same amount of catalyst as used in the TekShield Roofing Resin Basecoat and thoroughly mix.

KoverTek Standard GRP Roofing Topcoat needs to be applied quickly after adding catalyst as the curing process will have started and you have limited working time. Apply quickly using a brush or roller and ensure there is an even thickness across the surface of 0.5mm. A Wet Film Gauge can be used to measure the thickness as if the topcoat is applied too generously, it may crack and if it is too thin, it will not cure thoroughly.

System Notes

• These packs are for PROFESSIONAL USE ONLY
• Please refer to product Material Safety Data Sheets for advice on safe handling
• It is of extreme importance that protective gloves and eye protection are worn when handling all products
• Spills or splashes must be removed immediately – if allowed to dry, material can only be removed mechanically or with heat and/or harsh chemicals
• All wet components of this system are environmentally hazardous. Do not allow products to enter water courses, drains, sewers or the general environment
• Always use a minimum of 1% catalyst even in summer to ensure a thorough cure. On a hot day, this may mean mixing less at a time
• The maximum catalyst level to use is 4% - the cure time will not reduce with higher catalyst levels
• Never underestimate the effect of temperature. TekShield Basecoat and Topcoat will not cure at or below freezing and we recommend they should be used above 7.5°C
• TekShield Basecoat and Topcoats will cure a lot quicker in warmer conditions
• When applying TekShield Topcoats late in the day - add more catalyst to allow for the lack of sunlight but not above an addition level of 4%. Summer grade catalysts are available to help slow TekShield Roofing Resin Basecoat and Standard GRP Roofing Topcoat down on hotter days
• Remember any catalysed TekShield Basecoat or Topcoat left in the bucket will exotherm. Heat is generated as it cures and it should be left well away from other stored materials. If you are finished with the resin in the container water may be poured over it to supress the heat gain - do not use this once the water has been added

Disclaimer

The advice and information given in here is given freely and in good faith and is based upon data provided by KoverTek. This information is based on KoverTek’s extensive laboratory testing and experience, but KoverTek cannot test for every eventuality. It is the customers responsibility to ensure that the product is fit for their intended purpose. KoverTek cannot guarantee anything but the quality of the product and cannot be held responsible for the results obtained.