flat roof

Everything you need to know about buying a flat roof house

Lots of properties in the UK have flat roofs, whether it’s the whole roof or just an extension. People choose this kind of roof because it’s usually cheaper than the alternative, but they can run into problems.

Before you purchase a house with a full or partial flat roof, it’s important to consider these potential flat roof problems…

What is a flat roof house?

As you’d expect, a flat roof house is a house where the roof is level rather than pitched. They are considered ‘non-standard’ properties and this can make the buying process slightly more complicated than houses that are considered ‘standard’ (brick or stone walls; pitched roofs; and slate or tile roofing). 

What is a flat roof extension?

Sometimes, it’s not the whole house which has a flat roof but just part of it. A flat roof extension is when the extended part of the house has a flat roof. People often choose this as the cheaper option.

What are potential flat roof house problems?

While many flat roofs serve their owners perfectly well, there are numerous potential issues associated with flat roofs which can ring alarm bells with property hunters. Probably the most common issue with flat roofs is leaks. While many properties will suffer leaky roofs, due to their structure, flat roofs offer nowhere for the water to safely run. The water tends to go straight down into the roof itself.

Other issues include:

  • Mould and fungus
  • Watermarks
  • Growing vegetation
  • Pooling water
  • Snow build-up
  • Cracks
  • Incorrect roof angle exacerbating water pooling issues
  • Flashing pulling away from the edges as asphalt expands and contracts with changing temperatures

Why is hard to secure a mortgage on a flat roof house?

Flat roof properties are considered non-standard and this can make it difficult to get a mortgage. Lenders and insurance companies consider them as higher risk and, if you get a mortgage, you may face higher rates.

Which survey should I book for a flat roof property?

If you are interested in buying a flat roof property, you should definitely get a professional house survey carried out. Your surveyor will point out any current or potential future problems which can help you make important decisions.

For flat roof houses we’d recommend either a Homebuyers Survey (Level 2 Home Survey) or Building Survey (Level 3 Home Survey) to uncover serious issues.

Should I buy a house with a flat roof?

While flat roof houses can pose serious issues, there are plenty of homeowners happy with their flat roof properties. Ultimately, you need to weigh up the risks, be aware that you may face higher mortgage rates and costly repair bills, and decide if you love the property regardless. If so, there’s nothing stopping you from buying a house with a flat roof.

To help you make your decision, we’ve put together some pros and cons of flat roof houses compared to conventional, pitched roof properties.

Pros of buying a flat roof house

Cons of buying a flat roof house

The asking price may be cheaper You may struggle to get a mortgage/insurance and/or your rates may be higher
Cheaper to construct They have a shorter lifespan and will need expensive repairs/replacing sooner
Access is generally easier There are numerous potential issues, mostly associated with poor drainage
Internal space is maximised Watermarks and cracks can be unsightly/concerning
Some people prefer how they look You may find it harder to sell the property in due course

Keep these points in mind when property hunting to help you make a fully informed decision.

Get in touch

Whether you’ve set your heat on a flat roof house or are just weighing up your options, we’re here to help.

If you would like professional advice or to book a survey, please get in touch. Our team of Chartered Surveyors have years of experience and will be happy to answer all your questions.