What Counts as Non-Standard Construction — and Why Lenders Care
When buying a property, most homes are traditional brick and tile with a standard roof. But what happens if you fall in love with something a little different? Timber frame, steel frame, prefabricated concrete, cob, thatch, or older systems like BISF and Wimpey No-Fines are all considered non-standard construction. While they’re still mortgageable, lenders view them differently due to structural and resale considerations.
Understanding how lenders assess these properties is key to avoiding declined applications or valuation surprises.
Why Lenders Are Cautious
Non-standard construction carries long-term risks that affect lending decisions:
Durability and maintenance: Older timber frames or prefab concrete can deteriorate faster than brick, requiring more frequent inspections or repairs.
Resale risk: Lenders consider whether the property will be marketable in the future. Unusual construction types can limit potential buyers, impacting the loan-to-value (LTV) a lender is willing to offer.
Insurance availability: Some materials or designs can make obtaining affordable buildings insurance challenging, which is essential for mortgage approval.
These factors often result in lower maximum LTVs, stricter lender criteria, and fewer mortgage options compared with standard properties.
Common Challenges Buyers Face
Purchasing a non-standard home can introduce specific hurdles:
Mortgage declines if the construction type is unclear at the viewing stage
Valuations flagging potential structural or maintenance issues
Limited lender choice for certain unusual materials
Difficulty securing cost-effective insurance
Being aware of these issues allows buyers to prepare fully before applying for a mortgage.
Step-by-Step Approach to Securing a Mortgage
A structured approach improves the likelihood of approval:
Identify construction type early – confirm whether it’s timber frame, steel, prefab, thatch, cob, or another non-standard method.
Gather reports and surveys – obtain structural surveys, previous inspections, or any maintenance records.
Match lender criteria – ensure the lender is experienced with that specific property type and comfortable with the associated risks.
Proceed to valuation – the lender will assess long-term durability, resale potential, and insurance implications.
Secure the mortgage offer – if the property meets the lender’s requirements, an offer can be issued.
This approach reduces the risk of late-stage declines and makes the process smoother.
How We Help
We specialise in guiding buyers through mortgages for non-standard properties:
Pre-checking construction types to identify suitable lenders
Preparing applications with the correct documentation and surveys
Reducing the risk of delays or declined offers due to unusual construction
While not all non-standard properties are mortgageable, working with an experienced adviser improves your chances of success and keeps the process transparent.
Key Takeaways
Non-standard construction includes timber frame, steel frame, concrete, cob, thatch, and specialist builds like BISF or Wimpey No-Fines. Lenders assess long-term durability, resale risk, and insurance availability, which often limits maximum borrowing.
By confirming the construction type, gathering reports, and matching your property to a suitable lender, you can secure financing for your unusual home with confidence. Understanding the process upfront avoids surprises and helps you make informed, realistic decisions.
