1. What will I repay in total?
This is the most important number. The headline loan amount is not what you pay back. The total is the loan plus all interest over the full term.
The GOV.UK factsheet gives a worked example: a £10,000 loan at 8% interest over 7 years costs around £155 a month. Multiply that out and the total repaid is roughly £13,020, meaning the interest adds about £3,020 to the original borrowing.
Before you agree to anything, ask the lender for the total amount repayable, not just the monthly figure. A lower monthly payment spread over a longer term can quietly cost you more in the long run. The scheme can offer interest rates up to 5% lower than standard personal loans, which is a meaningful saving, but you still need to see the full picture in writing.
Key question for your lender: "What is the total amount I will repay over the full term of this loan?"
2. How long is the loan?
Warm Homes Loans can run for many years, and some terms extend up to 30 years. A longer term reduces the monthly payment, but it also means you are paying interest for longer, and your financial circumstances can change significantly over three decades.
Think about how long you plan to stay in the property. If you move, you will need to understand how the loan is handled, whether it is repaid from the sale proceeds or transferred in some other way. The scheme does not specify how this works, so ask your lender directly before you commit.
Match the loan term to your plans for the property, not just to the lowest monthly payment.
3. Are there fees on top?
GOV.UK advises checking the total amount repayable, the length of the loan and any monthly fees, but interest is not the only cost a lender can charge. Watch out for:
- Arrangement fees added at the start
- Administration fees during the term
- Early repayment charges if you want to pay off the loan ahead of schedule
- Late payment fees if a direct debit fails
None of these are ruled out by the scheme. Always ask for a full schedule of fees before signing, and read the loan agreement carefully. If you want to overpay or clear the balance early, ask specifically whether there is a penalty for doing so.
4. Is my installer MCS-certified?
This one is non-negotiable. The Warm Homes Loan scheme requires your installer to hold MCS certification (Microgeneration Certification Scheme). Without it, your installation will not qualify and the lender will not release funds.
MCS certification is not just a tick-box for the loan. It means the installer has been independently assessed for technical competence, that the products they use meet quality standards, and that you receive a formal MCS certificate after installation. That certificate is also what you need to claim the Smart Export Guarantee (SEG) tariff, which pays you for surplus electricity exported to the grid.
Djuka Electrics is MCS-certified and NAPIT-registered. You can verify any installer's MCS status for free on the MCS installer search.
5. Does the lender only work with certain installers?
Some lenders partner with specific installers and will only release loan funds if you use one of them. Others will accept any MCS-certified installer. This is a question to ask every lender you approach:
"Will you release funds for any MCS-certified installer, or do I have to use one from your approved list?"
If a lender's partner installers do not include the installer you want, choose another lender that accepts any MCS-certified installer. If you would like Djuka to fit your system, this is the first question to ask. The scheme is government-backed, but the individual loan products are offered by participating lenders who may each set their own conditions.
6. Is my quote written and itemised?
Lenders will want to see your installer's quote as part of the application. A vague or verbal estimate will not do. You need a written, itemised quote that sets out exactly what is being installed, the make and model of every product, and the full cost broken down by component and labour.
An itemised quote protects you in two ways. First, it gives the lender confidence that the loan amount matches real costs. Second, it means you know precisely what you are paying for and can hold your installer to it.
Djuka Electrics provides free written quotes with no hidden costs as standard. Every quote is written and itemised, so there are no surprises when the invoice arrives. If your installer cannot or will not provide this level of detail, that is a warning sign worth heeding before you borrow.
Note on VAT: Solar panels and home batteries currently attract 0% VAT, a rate confirmed until 31 March 2027. Your quote should reflect this. Check that VAT is shown correctly before submitting to a lender.
7. What paperwork will I get?
A completed solar or battery installation should come with a clear paper trail. Before the loan funds are released and before your installer leaves site, make sure you know what documents to expect and when.
From your installer
- Written MCS certificate confirming the installation meets scheme standards
- Electrical Installation Certificate (EIC) or Minor Works Certificate, signed by a registered electrician
- Manufacturer warranties for panels, battery, and inverter
- Itemised invoice matching the original quote
From your lender
- Loan agreement setting out the interest rate, term, total repayable, and all fees
- Direct debit mandate or payment schedule
- Details of any cooling-off period
Keep all of these documents somewhere safe. The MCS certificate in particular is needed if you ever apply for the Smart Export Guarantee, sell the property, or make a warranty claim. If your installer is slow to provide paperwork, chase it in writing before you authorise final payment.
Is the Warm Homes Loan worth it?
For many homeowners, yes, provided you go in with clear numbers. The scheme offers rates meaningfully below standard personal loans, the loan limits of up to £15,000 for solar and £15,000 for a battery are generous, and the 0% VAT rate until March 2027 reduces the total cost further.
The honest caveat is that the loan still costs money. Interest-free products may be available to some applicants, but others will pay interest for years. Run the total repayable figure against your expected energy bill savings before you decide. GOV.UK's example shows the scheme could save up to £285 a year on repayments compared with a loan available today. Any savings on your energy bills are separate and depend on your tariff, your usage and how much of your solar electricity you use yourself.
The scheme is not a grant. It is a loan with credit and affordability checks. If you are not approved, or if the terms offered do not stack up, there is no obligation to proceed.
Planning to use the Warm Homes Loan? Start with a free, written Djuka quote, the document lenders ask for.
Key figures at a glance
| Item | Key fact |
|---|---|
| Maximum for solar panels | Up to £15,000 |
| Maximum for a home battery | Up to £15,000 |
| Interest rates | Up to 5% lower than regular loans |
| GOV.UK example | A standard £10,000 loan at 8% over 7 years is about £155 a month |
| Saving through the scheme | Up to £285 a year on repayments, in GOV.UK's example |
| VAT on solar and batteries | 0% until 31 March 2027 |
| Who can apply | UK households only |
| Installer requirement | MCS-certified installer |
| Finance checks | Credit and affordability checks apply |