It is best to try and ensure that all roof repairs are undertaken when the weather is good and there is no prospect of rain for at least a day.

Most of these waterproofing solutions can withstand light rain within a few hours, but will obviously cure better if left to dry for about five to seven days. Before starting any roof repairs, inspect the roof thoroughly, in order to pinpoint the problem area. It helps to get into the ceiling space with a torch and inspect for telltale water stains of roof trusses or floor sheeting.

There are a number of problems that cause leaking roofs. During your inspection look out for damp, mouldy or cracked parapet walls; cracked or displaced flashing, (the area between the roof surface and parapet walls, chimneys or skylights); loose lap joints and popped roofing bolts.

If you come across any of these signs, it's worth taking action to rectify the problem. Untreated problems could result in severe damage in the long term. Consider a step-by-step DIY brush-on solution as well as four membrane solutions and get your roof looking as good as new.

Brush-on waterproofing solutions can be used to tackle damp, mouldy or cracked parapet walls. Waterproofing membrane solutions can be used to tackle cracked flashings, loose lap joints, popped roof screw bolts or roof screw holes and cracked parapet walls.

PROBLEM: Damp, mouldy or cracked parapet walls

Water can trickle through a cracked parapet wall creating damp and mould (pic 1).

Solve the problem by following this step-by-step guide:

? Prepare the surface - use a wire brush to remove any loose or peeling paint until you achieve a sound surface. You should also remove any signs of dirt, grime or dust (pic 2).

? Apply a single coat of waterproofing primer to the prepared surface (pic 3). This is especially important when you are working on porous surfaces such as concrete and will ensure better product adhesion. The primer should dry within minutes, if conditions are warm.

? Pour the Flash Harry Fibre Flex onto the prepared area (pic 4) and use a roller to spread it evenly across the surface (pic 5). Make sure that the fibres are evenly distributed and that you're left with a 1mm thick film.

However, if you are using Everbond Colour & Seal apply the first coat, let it dry for two hours and then apply the final coat.

? If you have used Fibre Flex the treated area will be resistant to light rain within eight hours and fully cured in seven days. Colour & Seal on the other hand will be resistant to light rain within four hours and take five days to cure.

? Once your roof is cured (pic 6), apply an acrylic paint in the colour of your choice.

PROBLEM: Cracked flashings

A cracked roof flashing is bound to cause leaks in your home (pic 1). This is how to fix the problem:

? Ensure that the surfaces to be water-proofed are clean, visibly dry and free of loose paint or plaster as well as dust, dirt and grime.

? If you are going to be using Alcolin Vinoseal, remember to stir it well before use and if it is thick, to add methylated spirits as necessary, in order to thin it down.

? Apply a generous coat of Alcolin Vinoseal, allowing for an overlap of 5cm either side of the membrane. ? Immediately embed the Alcolin Membrane into the coating - only work in small sections at a time, as Vinoseal tends to dry quickly.

? Finish off by applying a second coat of Vinoseal. Once the area has dried, check for any uncovered areas and re-coat them.

? If you have chosen to use EverEasy, make sure that you apply enough of the first coat to allow for initial bonding (pic 2).

? Put on the gloves provided and then remove the lid from the plastic EverEasy container and lift out the membrane.

? Place the lid back onto the container and reseal it along three sides of the top of the container, allowing sufficient space to pull the membrane out of the DIY kit. ? Pull the membrane out of the kit and then apply it to the area requiring waterproofing. Make sure that you remove any excess liquid and that you work all the bubbles and creases out of the membrane (pic 3).

? Cover the area with the required length of membrane, before cutting the membrane with scissors.

? Allow this area to dry for two hours (weather permitting). ? Using the product left over in the bucket, apply the final coat of EverEasy to finish the waterproofing.

PROBLEM: Loose lap joints

A loose lap joint can result in water trickling through your roof (pic 4). Here's how to tackle the problem:

? Make sure that the joint to be waterproofed is free of all grease, oil or loose and flaking particles. You should then clean and wash it, allowing sufficient time for it to dry.

? Prime the surface with a suitable metal primer. This will not only to give the surface excellent adhesion properties, but also help it to resist rust.

? Brush or roll on a thickish coat of super laycryl (pic 5).

? Bed the membrane into the wet coat by using a roller or a stiff brush.

? However, if you are working on a flat surface, you should rather use a fluted aluminium roller. Bear in mind that the membrane overlaps should be a minimum of 75mm on end laps and 50mm on side laps. You should also make sure that there are no bubbles or wrinkles in the membrane.

? Allow the first coat to dry for two to three hours, depending upon the weather.

? Apply a second coat of super laycryl to ensure that the membrane is completely saturated (pic 10).

? Once the second coat is dry, apply a finishing coat of super laycryl at right angles to the second coat.

PROBLEM: Popped roof screw bolts or roof screw holes

Water can seep through popped roof screw bolts or holes (pic 7). This is how to fix it: ? Use a wire brush to prepare the surface and then tighten the roof bolts where possible.

? Apply the primer and first coat of Flash Harry One Shot over the bolts (pic 8). Cut the Flash Harry One Shot membrane into squares of 75mm x 75mm. If the roof bolts protrude excessively, cut 15mm slits into each side of the square, in order to prevent wrinkling and possible leakage.

? Press the membrane square into the first coat and then apply two finishing coats (pic 9). Note: the area will be resistant to light rain within eight hours and will take approximately seven days to cure properly.

PROBLEM: Cracked parapet walls

A cracked parapet wall beside a tiled roof can result in water trickling through the crack (pic 10). Overcome this problem by following these step-by-step instructions:

? Before you fix the leak, repair all defects such as broken tiles, rusted metals or missing nails. Also ensure that the surface you are going to repair is dry, firm and free of dirt, loose paint, oil and grease (pic 11).

? Stir the RoofSeal thoroughly before use.

? Dilute the first coat of RoofSeal with 50% water and then apply it to the surface with a brush or roller (pic 12).

? Allow it to dry for two hours, before applying a second coat of RoofSeal (unthinned) (pic 13).

? Imbed the RoofSeal membrane in the wet coating immediately, ensuring that the membrane is completely wetted with the RoofSeal. Remember to apply the third coat of RoofSeal before the second coat dries completely (pic 14).

? If you are using Duram Rainkote, apply a thick basecoat and then press the Duramesh firmly into the wet Rainkote.

? Allow this to dry, before saturating the Duramesh completely.

? You can now either apply two further coats of Rainkote or one coat of Rainkote and one coat of exterior acrylic paint to serve as a topcoat.

Waterproofing solutions

There are a great number of products available which you can use to waterproof your roof. Consider the following options:

? Everbond. A non-toxic, fibre-reinforced, acrylic waterproofing, which has good UV resistance and elongation properties. This makes it ideal for most waterproofing applications such as hairline cracks, parapet walls and roofs. Available in black, brown, green, grey, historical green, red, terracotta and white.

? EverEasy waterproofing kit. This acrylic water-based system consists of a pre-saturated membrane supplied with liquid, which is used as a first and final coat. This sealant can be used to waterproof flashings, roof valleys, lap joints and screw heads due to its UV resistance, low water uptake, elongation and tensile strength properties. Available in black, grey, historical green, red, terracotta and white.

? EverSeal. A water-based acrylic system from Everbond for use with a membrane. EverSeal has excellent UV resistance and low water uptake properties, which means that you can use it to waterproof flat concrete roofs, corrugated iron roofs, overlapping roofs, flashings, roof valleys and parapet walls. Available in black, grey, historical green, red, terracotta and white.

? Fibre Flex. Flash Harry's acrylic and reinforcing fibre blend forms a quality flexible non-slumping and viscous membrane-free waterproofing compound. It is suitable for use on parapet walls, repairing tiled roof cappings and cracked tiles, sealing of lap joints and roof bolts (use with membrane) as well as many different details on iron, tiled, concrete, timber and asbestos roof surfaces. Available in black, blue, brown, green, grey, red, terracotta and white.

? Flash Harry - One Shot. A homogenous flexible and seamless, water-based acrylic waterproofing system that can be used for many different details on iron, tiled, concrete, timber and asbestos roof surfaces such as sealing lap joints and roof bolts, parapet walls and all types of flashings. Available in black, brown, green, grey, red, terracotta and white.

? Polycell RoofSeal. This water-based acrylic dries to a highly flexible UV and weather resistant waterproofing system. You can use it to waterproof parapet walls, leaking roofs, flashings and non-traffic flat roofs. Available in charcoal, green, slate grey, tile red and white.

? Rainkote. Duram's water-based acrylic dries to a highly flexible UV resistant waterproofing system. You can use it to waterproof pitched roofs, parapets, flashings and roof screws. Available in black, brown, charcoal, green, grey, red, terracotta and white.

? Rainseal. An acrylic-based emulsion coating from Alcolin that is UV resistant and contains a fungicide. For waterproofing applications on galvanised and asbestos roofs, concrete parapets and flashings it should be used in conjunction with an Alcolin Waterproof Membrane. Available in black, green, grey, red and white.

? super laycryl. This highly flexible liquid emulsion is reinforced with an a.b.e. membrane to provide an in situ, seamless waterproofing system. It has excellent weathering and adhesion properties, and is also tough, flexible and non-toxic. All this makes super laycryl suitable for non-trafficable roofs, which means that it can be used for flat roof waterproofing, re-waterproofing over existing waterproofing systems, parapet walls, all types of flashings and sealing joints, laps and roofing screws on corrugated roofs. Available in charcoal, grey and red.

? super laykold. A rubberised bitumen emulsion, which must be used together with an a.b.e. membrane to provide a liquid waterproofing system. Its strong elastic, adhesion and saturating properties means that you can use it to seal the joints, laps and roofing screws on corrugated roofs as well as for flat roof waterproofing areas, flashings and parapet walls. Available in black.

? Vinoseal. Alcolin's liquid vinyl coating system dries to form a non-toxic, flexible plastic film that is 100% waterproof. Bear in mind that it is designed for use as a durable maintenance waterproofer on flat and pitched roofs as well as flashings. Available in aluminium, cloud grey and white.