What Is A Non-Standard Property And Should I Consider Buying One?


We’ve all seen TV programmes and stories in the media about unusual buildings – places which stand out from the ordinary because of their design, location, age or construction materials. Usually, these stories dwell on appearance and idiosyncratic features but they don’t always drill down into the details of what constitutes a ‘non-standard’ construction for the purposes of insurance.

What is a non standard property?

Here’s a look at some of the building profiles which are classed as non-standard constructions, as well as a quick low-down on why they’re non-standard.
Thatched properties can be expensive to repair and pose a risk of extensive fire damage so they require specialist non-standard home insurance cover.
Houses with flat roofs are more likely to leak and suffer weather damage. They’re also easier for thieves to gain access to, so some insurers don’t cover them.
Listed buildings are often over 100 years old so they are expensive to repair because they need traditional materials and methods.
High-value homes over a certain value or size (more than six bedrooms, usually) often need a non-standard home insurance policy.
Unusual construction properties refer to material or build type. For example, steel frame or timber. These are pretty expensive to repair.
Flood risk areas mean complications when getting insurance because whatever the property, there’s an inherently greater risk being assumed by the insurer.
Prefabricated concrete houses were built after the end of the Second World War as what was supposed to be a stop-gap measure to provide people whose homes were destroyed in the Blitz with affordable housing. There are currently just over one and a half million concrete prefabricated homes in the UK and these require non-standard home insurance.

Common materials used in non-standard construction

A non-standard construction uses materials that don’t conform to the ‘standard’ definition (brick or stone walls with a roof made of slate or tile). A non-standard construction is basically anything that falls outside of this definition.
Non-standard homes are often found in common geographical areas where the construction materials are (or have always been) more easily available. There are two elements of the building which can be construed as non-standard; the frame and walls is one and the roof is the other. The following are examples:

  • Walls made out of glass
  • Walls constructed of concrete
  • Walls constructed of metal
  • Wooden walls
  • Woodwork frames for the house
  • Flint stone walls
  • Corrugated iron walls or frames

Materials often used in non-standard construction include things like:

Steel frames

Steel frame houses are characterised by their ease of construction, their lightweight, and their affordability. Nevertheless, steel frame constructions can be both difficult and expensive to insure, as it can be very expensive to repair if anything goes wrong. They are considered as not being particularly flame resistant, meaning if there is a fire the heat can cause the steel beams to warp. In turn, this can obviously cause big structural problems for the whole property. structure.


BISF houses are steel-framed houses built by the British Iron and Steel Federation from 1946 onwards. There are a number of factors that can make insuring them problematic. Firstly, almost all BISF houses were built with corrugated asbestos, cement or steel roofing sheets. Over time these sheets have suffered from deterioration with most showing signs of erosion.


Timber Frame

Timber-framed homes are regarded as complex or ‘non-standard’ properties, with the consequence being an increase in premiums to cover the risk. This is particularly the case when looking for insurance for an old timber-framed home because of its susceptibility to fire.


Prefabricated houses largely came into use after the Second World War. Following the devastation of the Blitz they were built off-site as temporary homes. Because of this construction method, they can be expensive to repair if damage occurs, as whole sections of the structure frequently have to be replaced.



Concrete homes often also fit into the category of prefabricated buildings as concrete is the commonest material used in their building. However, some properties are constructed from concrete blocks as opposed to prefab slabs. This makes them a different kind of risk because concrete walls can begin to crumble as they age, and cracks may begin to emerge as the steel binding rods holding the walls together begin to corrode.
There’s no hard and fast way of knowing how long it might take for problems caused by materials to emerge but clearly, the known susceptibility of the material can cause an unfortunate chain of events. It’s more difficult for an insurance underwriter to assess the risk. Consequently, it can be difficult for you to get insurance on non-standard properties. It therefore also becomes harder to secure a mortgage to buy such a property and, in turn, this can make it difficult to sell on.

Buying (and selling) a non-standard property

 Large white house with purple flowered  garden
People have all manner of motives for buying a non-standard property. They may want to:

  • stand out from the crowd
  • make a long-lasting dream come true
  • renovate a crumbling edifice to look like a castle once more
  • retire to somewhere unusual

These are all perfectly understandable and legitimate reasons for buying somewhere to live which isn’t simply a carbon copy of thousands of other dwellings. Of course, there is a big BUT. Non-standard options can cause a variety of complications regarding finance, warranties, insurance and selling the property on.
Naturally, if or when it comes to sell the property in the future, current choices impact on any future buyer. Choosing an alternative build might make sense for you right now, but you’ll have to live with the implications for years to come. You might be forward-thinking and appreciative of left-field structural systems, but will your lender, and your future buyer’s lender? You will be confronted by additional mortgage and insurance costs (and certainly higher labour costs), but also your home’s future buyer (or, more to the point, their solicitor or lender) may well be discouraged by your offbeat choices. But don’t let all of that put you off!
The local market and location is also a consideration, and if a particular form of construction or non-traditional element is deemed unusual or rare for the area then it is more likely to affect the saleability. Of course, if your property is in keeping with other properties in the local area, then your saleability and value are much more secure.

A structural warranty

Getting a full structural survey before you buy the property is a must.

  • Find out when, why and how it was fixed.
  • Speak to your lender and insurance broker before you buy the property.

For previously underpinned properties you should speak to a specialist BIBA broker who can help you arrange cover.
If you are planning on using an alternative form of construction or material, get a full 10-year structural warranty. This will help when it comes to selling your property, as it will give the buyer’s lender assurance that the property has been built to acceptable standards.
It’s important to check the warranty cover thoroughly so you know what is included, as not all providers will offer the same level of cover. Typical costs for a warranty with full technical audits are around £1,500-£1,800, but this is a wise investment, especially if you know that you will be selling the property at a later stage (even if that’s after the warranty expires). The warranty will help potential future buyers when trying to get a mortgage. Some banks and building societies may be reluctant to provide funds for new or newly converted properties less than 10 years old unless there is a structural warranty in place.

Money, money, money

When it comes to funding your project, building anything other than a ‘standard’ bricks and mortar home needs some serious thought, as it can have a major impact on the range of finance and insurance options you will have to choose from. If your project involves anything classified as ‘non-standard’ – from the construction material, to roofing or cladding – then you are moving away from simple, generic financial products and into ‘specialist insurance’ territory, where self-build mortgage, buildings insurance and warranties tend to come at a premium.
When buying a non-standard property, there are a few steps you can take to make the whole affair less daunting:

  1. You’re buying something which is often sold at auction. Make sure you know exactly what a house is made of before you make a bid.


  1. You may have to sell the house at a lower price than usual to attract a potential buyer in the future. Plan accordingly for any additional conveyancing, legal or mortgage costs.


  1. Finding an insurer prepared to sell you the non-standard home insurance that you need will take a bit of research, so set aside some time for that.


  1. Find a specialist legal company to carry out the conveyancing, preferably someone local who has experience of additional questions that may need asking. 


  1. Get an estimate of what the bills will be. For example, how much will it cost to heat?


  1. If the property needs renovating, find builders with experience of renovating properties like yours.

Incidentally, when it comes to selling on, non-standard construction properties can be turned into ‘standard’ either by securing planning permission to demolish it and then rebuild it, or by alteration work such as removing concrete panels and replacing them with bricks and mortar.

Non-standard home insurance

So, as we’ve seen above, if your property is built with non-standard materials, you may find it hard to get insurance from a general insurance provider. They may not have the specialised knowledge to judge the risk or perhaps it is simply objectively difficult to judge. When insurers are unfamiliar with the actual risk, they will usually either charge too much for premiums or refuse to offer quotes altogether in order to protect themselves.
If providers are willing to cover you, it can often result in prohibitively high premiums and excesses. This is why it’s well worth coming to the specialists like Insurance Choice to see if we can find you the most competitive premium and excess quotes.

Dealing with subsidence

If there’s one word that causes cold chills for a homeowner, it’s ‘subsidence’. When considering buying a non-standard property, many buyers ask themselves “can I get non-standard insurance if there’s evidence of subsidence?”
Most household insurance policies cover loss or damage caused by subsidence, heave and landslip. But they only cover the cost of repairing the loss or damage, not the cost of preventing more subsidence. The UK is one of the only countries in the world that insures private homes for the risk of subsidence, heave and landslip.
Expect the excess to be higher though, as subsidence claims are generally more costly to the insurer. An excess figure of £1,000 is typical. Make sure you’re completely honest about having made a previous subsidence claim. Doing otherwise could see future claims turned down. Either way, you’re likely to see an increase in your monthly premiums.
As specialists in this area, Insurance Choice know about varying building categories and other circumstances requiring non-standard home insurance. Rather lesser-known items in the list of obligatory non-standard insurance include:
Criminal conviction: If the person living in the property has a criminal conviction, non-standard house insurance is obligatory.
Unoccupied property: If you are not living at the property (as opposed to it being empty while you sun yourself in the Caribbean), then you need to get non-standard insurance.
Adverse claims history: A person who has made a large number of claims (or a small number of high-value claims) in the past. Generally the result of simple bad luck,  but unfortunately, it means non-standard insurance might be the only option.
It pays to be well-informed when it comes to non-standard home insurance. As we’ve already seen, the incremental costs of buying a non-standard property are going to be significantly higher than average, so make sure to access our expert advice when deciding on your insurance coverage and calculating your costs.