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PermaRoof UK stocks a range of easy-to-apply products for re-roofing your flat roof extension. Get expert advice, quality products and how-to guides or find a local extension roofing specialist today.

We support both trade and DIY with quality products, including EPDM flat roof extension kits to make sure your new project is fully watertight. With innovative, modern extension materials and a wide range of step-by-step installation guides via video and download, PermaRoof UK really is a one-stop-flat-roof-shop.

Our experienced team is on hand to guide you through your DIY projects and help you choose the right extension roofing products. If DIY isn’t for you, let us connect you with a recommended, local flat roof extension installer via our National EPDM Installer Network.

If you have decided to investigate the prospect of a flat roof extension to your property, there are several points to consider, even if you are enlisting the support of a project manager or architect. There are many benefits to be gained in extending a current house, rather than experience the cost and upheaval of moving to a new one.

However, it is all in the planning. PermaRoof UK is here to help with a wide range of advice about many aspects of your project. EPDM flat roofing experts, we also provide a selection of some of the most innovative systems available on the market today.

What is a flat roof extension?

It’s all in the name with a flat roof extension. Unlike pitched roofs which angle steeply down to collect and deal with water in a guttering system, a flat roof extension simply uses a flat roof (with a slight angle) that can also deal with drainage and water control well.

A flat roof, however, is never truly flat and never should be. A minimum gradient of 10% is enough to constitute a flat roof. This is an important part of the roofing design to avoid pooling water which can create vulnerable points and compromise the structural integrity.

Why extend?

Extending a property to create additional living space has become more and more popular with homeowners in recent years over moving to a new house. The most common reason is simply cost.

Once homeowners have factored in stamp duty, estate agents’ fees and removal costs, moving to a new house can be considerably more expensive than expanding your existing property in the current financial climate in the UK.

Key Considerations

Design considerations

It’s important to consider how you will use your extension. Moving your kitchen or bathroom, for example, may require a different design than an extra bedroom or office. Think about aspects such as how big you want the space to be, whether you would like one or two storeys, and the cost impact of these decisions.

Long term use of space

Also think carefully about your use of the extra space long-term. For example, you may need a playroom for your children right now, but what would you use the room for in the future when they have moved out? A two-storey extension will not cost double the amount of a single storey, as a lot of the overall cost comes from the groundwork.

Think practically about your flat roof extension

The use of your extension may drive the materials that you use for the main structure, such as bricks or wood. It may be an option for you to use a pre-built structure that is simply slotted into place. Whilst you may have a dream design idea, or seen something that you would like to replicate, this may not be practical for your property.

Does size matter?

When planning a home extension project, make sure to think carefully about the additional floor and living space you need. This is often where architects can come into their own during quantifying and calculating budget within the design. A two-storey extension, for instance, may work out to be a more cost-effective option than a single in the long-term, especially if you think you may need the space later. This can make a difference in terms of saved labour expenses and materials discounts.

Large Flat Roof Extensions

Large flat roof extension projects require detailed planning, and it is important to make sure to factor in a contingency in both time and cost. The scale of works could also mean you may wish to move out of your property while the extension is being completed. These are seemingly small, but important details that should be considered.

Small Flat Roof Extensions

Small flat roof extensions, such as porches, balcony extensions or extensions to garages can often be comfortably handled with a skilled DIY approach. EPDM kits are perfect for a small extension flat roof as they can be laid in a single sheet, simplifying installation and offering a complete seal across the roofing.

Busting the myths with modern flat roof extensions

In the 1960s and 1970s flat roof extensions gained a bad reputation due to many developing leaks and essentially not doing their primary job of keeping the inside of the building dry. They were often ugly concrete buildings or poorly constructed lean-to arrangements. This bad reputation stemmed from the reliability of traditional roofing materials of the time and the methods used to build them. Those materials and building methods are now barely recognised on the flat roofs of today.

Extensions in modern times are stylish, practical and well-designed additions to the home, requiring planning permissions and inspections, and quality standards in both materials and building methods. Today’s flat roof extension projects are much more likely to deliver a return on investment and add value to the overall property price.

How much will a flat roof extension cost?

Along with your design, the costs for your flat roof extension can be make or break. Make sure that you understand how the costs are comprised for your chosen design, and where costs could be saved. For a complex design or non-standard property, it may be beneficial to employ a structural engineer or architect.

Whilst this may be an initial cost, they should be able to advise you on where you can save money if you need to. Don’t be afraid to challenge if the design is not to your liking or the scope of the project is creeping. At all times, consider how much value you are adding to your property in comparison to the amount you will be spending. It may be that a larger cost upfront pays off in the future.

If you are confident in your DIY skills, there will be opportunities for you to save money during the project, such as installing the extension flat roof waterproofing. Be realistic and tackle jobs you know you can do well, as mistakes can prove more costly in the long run when professionals need to be called in to rectify them.

Planning Permission

Many flat roof extensions will require local authority planning permission. Planning rules are complex, so it is a good idea to start with your local council website for the Permitted Development Rights in your specific area. Around 90% of planning decisions are dealt with by local planning offices, so getting them involved in your plans as early as possible can be beneficial. Starting work without acquiring the correct permissions can work out very costly in the long run, so make sure you factor in plenty of time to your plan.

It can work out to be greatly beneficial in the long run to speak to your neighbours at the start of the process, even when you are weighing up some design options. This allows them to voice any strong concerns they may have, so that you don’t waste any design time. It also means they should be more amenable during the planning permission stage.

A Plain English Guide to the Planning System – is available to download at the UK Department for Communities and Local Government here.

Building Regulations

Note that Building Regulations are different from Planning Permission, and compliance will be required at every stage. Expect unplanned visits from Building Control Officers during the project, who will inspect major build works at regular intervals. If you are concerned about work being carried out on your project at any time by any contractor, you may contact them to arrange for someone to come out.

Many homeowners choose to complete flat roof extension projects themselves to save money during the final stages. While many common DIY tasks can include decorating and finishing inside, modern flat roof extension materials and systems have made historically more complex tasks much easier and safer to carry out.

For the confident DIYer our easy to apply extension flat roofing kits and detailed step-by-step tutorials make working on the roof waterproofing fast and easy. EPDM membranes are often laid in a single sheet using cold applied installation methods, for example, making these types of projects straightforward, while offering exceptionally high performance. We can support you in your project from the start – help you select the right flat roof extension materials in the right quantities and offer detailed installation guides in both video and PDF format.

Preparing the extension flat roof for membrane application

Preparation is also a key part of the installation process. If mistakes are made during this key stage, there is a risk that the membrane will not fully adhere across the flat roof extension.

Using a household broom, sweep away any loose debris from the surface of the roof and ensure that it is free from dust. If you are applying the EPDM over another material, make sure you have adequately prepared the surface and are using the correct adhesives.

Liquid PU rubber roofing is suitable for a wide range of substrates and may be a better choice for some types of flat roof extension projects. Talk to the PermaRoof UK Teams if you need advice or support with your order.

Further Reading

If you are looking at a DIY approach to your flat roof repair, you will need some basic tools and essential items. Repairing a rubber roof is often fast and easy if you’re well prepared.

Common Tools Required

• 2” silicon hand roller
• Penny roller
• Household broom
• 9” paint roller frame and medium nap solvent compatible roller covers
• Safety glasses and eye cleaning solution
• Mastic gun
• Crayon
• Screw gun and hammer drill
• Solvent resistant rubber gloves
• Stir stick for adhesives
• Tin snips
• Scissors
• Measuring tape
• Hammer
• Duct tape
• Cotton rags

Flat roof leak repair products

A leaking flat roof needs to be addressed quickly to avoid damage to the roof structure, interiors and goods stored inside.

PermaRoof UK stocks a wide range of easy-to-apply products to help with all types of flat roof repairs. Some flat roof issues will require only a patch repair, particularly if the damage is spotted early enough.

Another common problem can be poorly sealed or failed flashing, which can quickly lead to damage. A flat roof flashing repair can often be quickly and easily handled by a confident DIYer, saving time and keeping the costs down. Whatever your problem, we’re here to help every step of the way with a range of high-quality products – EPDM patches, flat roof repair tape, adhesives, tools and much more.

Talk to us if you need expert advice about your flat roofing repairs and we’ll even help you choose the right products for the job.

Professional Roofing Repairs or DIY?

It is worth reminding yourself that you are working at height and could be injured even if working on a single-storey garage flat roof repair. Falls from height are common in the DIY sector, and safety should always come first.

If you aren’t confident working at height as a DIYer, realise your limits and call in a professional roofer to carry out your flat roof repair. An experienced roofer may not charge as much as you think for a simple repair to your rubber roof membrane, for example. Bear in mind that an emergency, out-of-hours call out will cost more than a scheduled, quoted repair.

Find a local flat roof repair specialist near you

If you’re looking for a reliable roof repair contractor, you’ve come to the right place. Through the nationwide PermaRoof UK EPDM installer network, it’s now much easier to find a reliable tradesperson to carry out your flat roof repairs.

PermaRoof UK EPDM training is industry-renowned and trade roofers completing our training courses receive certification. Because of this, we can confidently recommend someone local to carry out a flat roof repair.

Visit the PermaRoof UK Installer Network today to find a flat roof repair specialist near you. Our service is fast and completely free to use.

If your flat roof leak is too severe or there are multiple leaks, it may be time to replace it altogether. This can also be the case if the cost of the flat roofing repair simply makes more sense to look at a longer term approach.

PermaRoof UK can provide you with a complete kit that includes everything you need, not just to repair the flat roof, but to replace it altogether. This kit includes the highest quality EPDM on the market – Elevate RubberCover, plus all the adhesive, trims and fixings you’ll need. If it is a flat garage roof repair, a shed or other garden building, we have a range of standard roofing kits to replace a failing roof quickly and easily – even for inexperienced DIYers.

Fast and easy-to-apply solutions to all types of flat roof repair

If your flat roof is badly damaged or has multiple leaks it may be time to replace it altogether. We can provide you with a complete kit that includes everything you need, not just to repair the roof, but to replace it altogether. This kit includes the highest quality EPDM on the market – Elevate RubberCover, plus all the adhesive, trims and fixings you’ll need. If the roof needing repairs is a shed or garden building, we have created the perfect product to replace a failing roof quickly and easily – even for inexperienced DIYers.

Our PermaRoof in a Box® kit is a complete shed roof kit including RubberCover  membrane, spray contact adhesive and Bond and Seal sealant. All of this is packaged into 1 neat box, available in multiple sizes. Don’t see the size you need? Just ask us and we’ll create a custom kit just for you.

If you need to make roof repairs quickly PermaRoof UK Emergency Roof Repair may be the product for you. The emergency roof repair can be applied to weathered asphalt and bituminous surfaces, concrete, brickwork, fibreglass, felt, metal (galvanised and ferrous), amongst other materials. Even if it rains after application, the waterproofing will not be affected.

For roofing repairs with liquid membrane, we recommend Permaband Matting. It is embedded into a coat of Permaroof 100. Depending on the size and purpose of the area it can be used in joints, splits and reinforcing small areas, in upstands, gutters and wrapping outlets, corners or in larger sizes for on larger areas (main deck area) or higher upstands.

Flat roof repairs – Do-It-Yourself?

We stock a range of excellent products that can make light work of a flat roof repair for DIY. Liquid EPDM membrane can provide a quick, emergency seal that is effective and long-lasting. Such roof repair systems are ideal for the DIY market, as they are easy to apply and cure quickly without professional assistance. EPDM rubber membrane is also straightforward to repair using adhesives and patches in a similar method to repairing a puncture on a bicycle wheel.

While these types of rubber roofing membrane repair are straightforward to carry out, it is important to remember that the seal must be watertight and the patches you have applied, perfectly adhered. Critical repairs to flat roofing must be carried out to a high-quality and if you aren’t sure you can create a perfect seal, it is wise to call in a professional, insured roofer to repair the membrane.

Professional Roofing Repairs?

It is also worth reminding yourself that this is work at height, generally, even if on a single-storey garage. Falls from height are common in the DIY sector, and safety should always come first. If you aren’t confident working at height as a DIYer, realise your limits and call in a professional roofer to carry out your roof repair. An experienced roofer may not charge as much as you think for a simple repair to your rubber roof membrane. Bear in mind that an emergency, out-of-hours call out will cost more than a scheduled, quoted repair.

It is worthwhile keeping an eye on flat roofing around the home and outside buildings to avoid an emergency roof repair and the associated costs. A simple, visual inspection, particularly following inclement weather or storm conditions, can highlight areas that may require further inspection or attention.

We have a network of approved, qualified contractors available. Through the nationwide PermaRoof UK EPDM installer network, it’s now much easier to find a reliable tradesperson to carry out your flat roof repairs. PermaRoof UK EPDM training is industry-renowned and trade roofers completing our training courses receive certification.

Professional flat roofers are invited to join our installer network following completion of the training and a stringent vetting process, offering peace of mind in this free service for homeowners.

PermaGroup has established links with some of the biggest names in our industry thanks to our reputation of excellence. Read more about becoming a supplier or stockist here.