Roofing Services Kingston

Polycarbonate Roofing Sheets are mainly used on conservatories, but this highly durable material can also be used for glazing greenhouses, porch windows and much more. Polycarbonate is one of the strongest plastics available and the triple walled type is increasingly being used as a replacement for wired safety glass.

Polycarbonate has a natural tendency to expand and contract so it is fitted ‘loose’ in special glazing bars. This clip-in fixing method means that fitting it is often much quicker than traditional glazing, whilst resulting in a much nicer and more durable finish than traditional corrugated plastic sheets.

- Up to 200 times stronger than glass
- 5 times lighter than glass
- Shatterproof
- Flexible
- Transmits up to 90% of available light
- Built-in UV protection as standard
- Adds insulation
- Dual, triple or even five-walled types available

Despite its impressive strength, Polycarbonate roof sheets can be cut easily using a fine toothed saw (such as a panel saw). Apart from making careful measurements before you make any cuts, the main thing to remember is to always try to cut as close to one of the inner walls as possible. This will help to maintain the strength of the cut end.

It is also important to leave the protective polythene covering in place until you are ready to actually fit the sheet. The top and bottom end of the sheet will be capped when the sheet is whole. If you have to trim the sheet, try to make sure that the top end capping remains. The cut end should then be capped with breather tape (perforated self-adhesive tape, sometimes supplied with the roof sheets). A plastic cover bead can then be fitted over the tape to cap the end.

It is important to keep moisture from entering the flutes (the name for the tubes running the length of the sheet) as this can lead to problems after installation. Never store cut sheets outside or on wet grass.

The exact fitting method for polycarbonate roof sheets depends very much on where you buy it from and where you are fitting it. Assuming you are using it for a conservatory or car port roof, you will be fixing it using glazing bars. These generally need to be bought separately.

The Glazing bars are screwed along the centre of the joists, the polycarbonate sheet is cut to fit between them and laid into place. Careful measurement is essential when cutting sheets to fit between the glazing bars. Most glazing bars have a top and bottom section, with the bottom section screwed to the joist and the top section clipping on to it once the sheets are in place to ‘cap’ the joint. The sheets themselves are never actually screwed to anything. The glazing bars are designed to hold the sheet in place, whilst allowing for expansion in hot weather and contraction in cold weather.

Detailed instructions for fitting should be supplied with the ...

On a standard roof in older houses, the area where the tiles meet the gables ends of the house is called the Roof Verge . The verge acts as a seal and helps to hold the roof tiles in place. Over time, water damage, frost damage or the natural settling of the house can cause the mortar to crack and even fall out. If the damage gets worse it can quickly effect the integrity of the whole roof.

Small cracks in the mortar of the verge can be quickly and easily fixed by using a roof and gutter sealant. This is injected into the crack with the applicator and allowed to dry before being painted over (if required). You can buy sealant in several colours to match the mortar if it is to be left unpainted.

Remove any cracked and crumbling mortar with a hammer and chisel, taking it back until it is completely sound. Brush away any dust and small debris with a dry paintbrush. Mix up your mortar using a standard mix of one part sharp sand to 4 parts cement (it is also fine to use a pre-mix bag if you wish) and mix in some PVA adhesive to, following the manufacturers instructions. Making the mix slightly dry will make it easier to apply on the vertical surface.

Dampen the area to be filled with water, using an old paintbrush to get into all of the cracks and holes, and then brush it with a coat of PVA adhesive. Start to fill the holes with your mortar, working from the back of the hole or crack and knocking it in with the edge of the trowel to make sure that there are no air pockets. Gradually build up the mortar until it is flush with the surface of the gable end.

To finish off, smooth the surface of the mortar with the trowel and make sure that there are no ledges or horizontal ridges which might retain water and cause future problems. When the mortar is completely dry, paint it if required.

If your mortar roof verge is in very bad condition, it is worth thinking about replacing it with a Dry Verge system. Dry ver...