Case Study: £400k Interest-Only Second Charge Mortgage for High-Value Home Extension

When a client required fast and flexible funding to support a large-scale extension project on their high-value residential property, we worked closely with the lender to secure a tailored second charge solution that met both the project timeline and long-term financial objectives.

• Residential homeowner seeking funding for extensive renovation and extension works on a high-value detached property.

• Required a £400,000 interest-only second charge mortgage at 35% LTV.

• Property would become temporarily uninhabitable during the initial stages of the build.

• Client needed funding in place ahead of contractors commencing works.

• Sought a lender with a fast, flexible underwriting approach and an understanding of staged construction projects.

• Solution secured with a 3-year fixed rate, interest-only structure to support monthly affordability and future remortgage plans.

• Funding was secured within seven weeks of the initial enquiry, despite the complexity of the case and full valuation requirements

The Client:

The client was a residential homeowner looking to significantly enhance their existing 5-bedroom detached property through a substantial rear extension across both the ground and first floors. The planned works were expected to increase the property value from approximately £2.89 million to circa £4 million upon completion.

The Situation:

The client required £400,000 in second charge finance to fund the scope of works and was specifically looking for an interest-only second charge mortgage to preserve monthly cash flow during the build period. The client opted for a second charge mortgage rather than refinancing their existing first charge facility, allowing them to retain their competitive first charge rate while raising capital for the home improvement project.

A key challenge was finding a lender comfortable with the fact that the property would be temporarily uninhabitable while the initial stages of construction were carried out.

Timing was also critical. The client already had building contracts in place and required funding to be completed ahead of the scheduled commencement of works. The client therefore needed a lender capable of delivering a fast and efficient underwriting process, while also understanding the complexities of staged refurbishment works and the requirement for a full valuation.

In addition, the client wanted a 3-year fixed rate product that would allow them to maximise residual income during the term, with plans to refinance once their existing first charge fixed rate concludes in 2029.

Our Solution

We identified a specialist second charge lender with the appetite and expertise to support complex residential refurbishment cases involving significant renovation works and temporary non-habitable periods.

Working closely with all parties, we ensured the lender fully understood the scale of the extension project, the staged construction timeline, and the client’s long-term financial objectives. The lender adopted a pragmatic and empathetic approach throughout the process, enabling the case to progress efficiently despite the specialist nature of the request.

The case was offered and completed efficiently, with funds released in line with the client’s preferred drawdown timing to ensure the renovation works could commence as planned.

Benefits & Results:

The client successfully secured a £400,000 interest-only second charge mortgage at 35% LTV, providing the necessary funding to proceed with the planned extension and renovation works.

The lender’s flexible approach meant they were comfortable supporting a project where the property would become temporarily uninhabitable during the initial stages of construction.

By securing a 3-year fixed rate on an interest-only basis, the client was able to maximise their residual monthly income throughout the build period and into the medium term.

The funding was completed in line with the client’s preferred timeline, ensuring funds were available ahead of contractors beginning work.

Once completed, the works are expected to significantly enhance the property, increasing its value from approximately £2.89 million to circa £4 million.

The structure of the solution also positions the client well for a future remortgage once their existing first charge fixed rate comes to an end in 2029.

This case highlights Aria Finance’s ability to structure complex second charge mortgage solutions for high-value residential properties, including cases involving staged refurbishment works, temporary non-habitable periods, and interest-only requirements.