Many homes in the UK have flat roofs, either covering part or the entire property. With the growing popularity of home extensions in recent years, flat roofs are very common. But while they might be commonplace, flat roofs can cause issues with insurance which means some lenders are less inclined to approve a mortgage on a flat roof property. But that doesn't mean you can't mortgage a house with a flat roof.

In this article, we'll look at your options for flat-roof property mortgages, including the obstacles you might encounter with these types of properties and where you can get help finding a lender.

What is a Flat Roof House?

As you may expect, a flat roof house does not have the traditional pitched roof and is considered a non-standard property. Flat roofs are often popular because of their versatility and ease of maintenance. Plus, they offer an energy-efficient alternative to sloped roofs. However, they can be expensive to repair and have a greater risk of water pooling and leaking. It's common for flat roofs not to last as long as sloped roofs. Most standard flat roof membranes last between 20 and 25 years before replacing. However, a strong rubber membrane may last up to 50 years. But, if the property is of an older style with an asphalt flat roof, it'll likely need replacing much sooner, usually after ten years. Before buying a house with a flat roof, you must check the roof's condition with an RICS home survey.

What is a Flat Roof Extension?

As the name suggests, an extension is a way to extend the size of your home, and a flat roof offers a cheaper roof system for the new living space. Flat roofs are usually quicker and easier to install and can even give homeowners the additional option of a balcony or terrace. With the potential of extra space combined with their relatively cheap construction, a flat roof extension is a good alternative to moving to a large home. A flat roof extension may also add extra value to the property and make it more appealing to homebuyers. Before organising to have a flat roof extension on your home, speak to your solicitor for advice in case there are any planning permission issues to be aware of.

What are the Pros and Cons of Buying a House with a Flat Roof?

There are many advantages and disadvantages to flat roofs:

Advantages of Flat Roofs

  • Quicker and cheaper to build
  • Easier to access for maintenance and cleaning
  • Cheaper to build an extension with a flat roof
  • It can be used as a balcony or rooftop garden
  • Energy-efficiency

Disadvantages of Flat Roofs

  • Often have drainage issues
  • Shorter lifespan than traditional pitched roofs
  • Unreliable in cold weather
  • Requires more maintenance
  • Higher repair costs
  • Must be checked at least once a year
  • Debris can build up easily
  • Provides easy access to criminals, resulting in higher insurance premiums
  • Flat roofs can shift and buckle

Can I Get a Mortgage on a Flat Roof House?

Mortgages on flat roof properties can be harder to secure as these are considered non-standard properties. From a lender's perspective, flat roof houses are high risk and, if they are willing to lend on them, they may charge higher rates and a larger deposit. Non-standard homes such as this can also be harder to resell, which makes them an unreliable form of security for a lender. But despite these factors, getting a mortgage on a flat-roof property is possible. You may just find that your options are more limited. That's why it's a good idea to speak to an independent mortgage broker from John Charcol, who’ll be able to point you in the right direction.

Which Lenders Offer Flat Roof Mortgages?

While your mortgage options may be limited, some lenders will consider a mortgage for properties with a flat roof. For example, depending on your circumstances, you may be eligible for a Halifax mortgage flat roof. A Natwest mortgage for flat roofs is also available subject to the provider's lending criteria, including obtaining a satisfactory property valuation and putting down a larger deposit. Most flat roof mortgage lenders won't lend on properties where at least half of the roof is flat, although this is usually assessed case-by-case. Lenders will have serious concerns if the flat roof is over 40 years old, as it will be at greater risk of problems such as leaking, impacting the property's valuation.

What are the Potential Issues with a Flat Roof House?

Some of the potential problems that can arise with flat roof houses include:

Pooling Water

Over time, a flat roof will settle and create areas with a big enough dip for water to begin to pool. These dips on the roof can collect rain and snow and increase the risks of water penetration and leaks.

Risk of Leaks

Water pooling on a flat roof can weaken the roof's structure and cause leaks. This can sometimes be avoided by regular maintenance or by ensuring the roof is made of a durable material such as PVC, EPDM, BUR or GRP.

Incorrect Roof Angle

Despite their name, flat roofs aren't entirely flat. There must be a slight angle to enable rain to run off into the guttering. However, if the angle is incorrect, a flat roof will be at an even greater risk of water pooling and leaks.

Cracking and Blistering

Most flat roofs are built using asphalt, which can often blister from prolonged sun exposure. If you notice cracks or blistering on a flat roof, it may be that the roof needs replacing.

Higher Insurance Premiums

Due to the additional risks posed by flat roofs, insurance premiums are often higher with these types of property than those with a traditional pitched roof. The insurance cost can also depend on the material the flat roof is made from and how much of the property it covers.

Mortgage Restrictions

Some lenders have strict lending criteria regarding how much of a property can be covered by a flat roof. Before applying for a mortgage, you'll need to check this with your chosen lender.

If you’re considering purchasing a flat-roof house, you can use this information in your price negotiations.

What is the Life Span of a Flat Roof?

The average flat roof should last between 20 and 25 years before you'll need to replace it. Older-style flat roofs that are constructed from asphalt may require replacing much sooner, usually within ten years. Fortunately, if you choose to replace your flat roof with a rubber membrane, you can expect the roof to last at least 50 years. Today's flat roof membrane materials are much more durable and last much longer. For example:

  • PVC Flat Roofs- strong and durable and usually last for around 20 years, although they can be noisy in heavy rain
  • Fibreglass Roofs - made from glass reinforced polyester (GRP), they are very durable, lightweight, provide good weatherproofing and last for at least 30 years. They can also be noisy in heavy rain
  • Built-Up Flat Roofs (BUR) with Layers of Gravel and Molten Layer - last for 10 to 20 years, but installation can be messy, and the structure may require reinforcing first
  • Rubber Roofing Systems - durable and flexible, expanding and contracting according to the climate, but without blistering or cracking. These roofs can last for 50 years

How Can I Tell If Flat Roof Area May Be a Problem?

If you’re viewing a house with a flat roof, the best way to determine whether the flat roof is a problem is by looking at the roof's surface on a dry day to see if you can spot any abnormalities. Tell-tale signs of a leaking flat roof include:

  • The flat roof panels appear to have been patched up
  • Signs of dampness within the property include watermarked ceilings or walls, flaky plaster or a mouldy smell
  • Look for dirt and debris on the flat roof that may prevent draining
  • The flat roof is covered in grass, algae or moss

Any cracks or blisters on a flat roof must be dealt with immediately. Otherwise, they’ll eventually tear and allow water to get in under the flat roof's protective covering.

How Can a Property Survey Help When Buying a Flat Roof House?

Organising a property survey before you purchase a property with a flat roof is essential. A building survey or a homebuyer's report should highlight any issues with a flat roof. Flat roofs are cheaper and quicker to build than pitched roofs, but they also have a shorter lifespan, so you'll need to get them inspected regularly. A home survey will identify any signs of wear or damage to the roof, including water pooling, leaks or cracking. The surveyor can advise on any repairs needed, which a specialist contractor should carry out. Repairs to a flat roof can be expensive and will depend on the size of the area affected, materials, and location. Replacing a flat roof can cost over £1,200.

What Factors May Impact Your Eligibility for a Mortgage on a Flat Roof Property?

If you want to purchase a house with a flat roof, making sure you meet all the lender's other eligibility criteria is particularly important. Otherwise, you'll have a limited choice of lenders and potentially face higher rates. Flat roof mortgage lenders will consider the following factors when assessing your eligibility:

Deposit Amount

A larger deposit will reduce the loan-to-value (LTV) amount and could be a make or break for whether you can get a mortgage. As lenders consider flat roofs as higher risk, a deposit of at least 15% will increase your chances of being accepted for a mortgage.

Income and Affordability

Lenders will want to check that you have a sufficient income to cover your mortgage repayments. Most lenders cap loans to 4.5 times your annual income, although some lenders will go up to six. They'll also want to factor in the extra maintenance required for a flat roof as part of your affordability assessment.

Source of Income

Lenders will also consider where your income comes from when assessing your mortgage application for a flat-roof property. At John Charcol, we can help you find flat roof mortgage lenders more likely to consider all types of incomes.

Credit History

Bad credit history doesn't necessarily mean you won't be able to get a mortgage on a flat-roof property, but it will likely limit your options considerably. Lenders will want to look at the type of bad credit you have and how recent it is. You may need a specialist lender who is familiar with dealing with borrowers in your circumstances. An independent mortgage broker, like John Charcol, will be able to refer you to the right lender that can help.

Your Age

Most mortgage lenders have an age limit on borrowing. Many lenders won't approve mortgages for people over 75, although some will go up to 85. There are a few lenders that don't have an upper age limit at all, instead focusing on your ability to prove that you can afford your monthly repayments.

Is it Harder to Sell a House with a Flat Roof?

Properties with flat roofs are harder to sell than those with a traditional pitched roof. While there are certain advantages to a flat roof, many buyers still prefer the appearance of a traditional pitched roof. Also, properties with flat roofs can be difficult to get a mortgage on and be more expensive to insure, putting off buyers. But this will largely depend on the area of the house that's flat. If the property has a flat roof extension, it shouldn't be hard to sell the property, unless the flat roof is damaged and needs repair.

Should I Buy a House with a Flat Roof?

While there are certain drawbacks to a flat roof, that doesn't mean you shouldn't buy a house with one. It's important to remember that getting insurance cover for these types of properties can be difficult, leading to issues with finding a mortgage provider to approve a flat roof extension mortgage. This is due to flat roofs being of non-standard construction, which could make them expensive to maintain and harder to sell in the future, should the lender repossess the property and try to recoup its losses.

Depending on the property type and size of a flat roof, your lender may require a qualified surveyor to carry out a roof inspection of the property you’re looking to buy before agreeing to lend to you. They may also limit the area of the house that can be flat. An independent building survey with an RICS surveyor will give you peace of mind before you purchase. They will check for any issues with the flat roof and ensure there are no risks to the structure and no damage or potential problems that may crop up in the future. They’ll check the roof for:

  • The structure and quality of workmanship
  • Blistering and flashing
  • Thermal movement stress
  • Water pooling

Houses with flat roofs are often cheaper to buy than those with traditional pitched roofs, which means you could get a great bargain. Remember that you may have issues down the line regarding resale value if you decide to sell.

Buying a property with a unique feature, such as a flat roof, can make getting a mortgage much more challenging. If you’re considering buying a flat roof property, our team of independent mortgage brokers can help you find the right lender and mortgage for your circumstances. We have extensive experience in helping buyers secure mortgages for non-standard properties. To find out more about flat roof mortgages, contact us today on 0330 433 2927 or submit an online enquiry.

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