Existing TMW mortgage? Borrow £15k at 2.99% for green upgrades

The Mortgage Works (TMW) launched an Energy Efficiency Further Advance priced at 2.99% with no product fee, open to its existing TMW buy-to-let landlords. You can borrow between £2,500 and £15,000, up to 75% loan-to-value, on a two- or five-year fix. That sits roughly two percentage points below TMW's standard rates — around 4.85% today at 75% LTV on a five-year fix.

Every penny of the advance must fund energy-efficiency improvements, and TMW may check the work was done.

The product itself covers individual, large-portfolio and limited-company BTL alike. However, some HAVE TO use a mortgage adviser whilst others have the option to.

The maths on a full £15,000, shown interest-only just to compare rates:

• At the 2.99% green rate: about £37 a month in interest.
• At the ~4.85% standard rate: about £61 a month.
• That is roughly £23 a month, or £280 a year.

The interest saving is nice, not transformative. The real value is access. Fifteen thousand pounds of cheap, secured funding for work most landlords have to do anyway — far cheaper than an unsecured personal loan (typically 8% or more), a second charge, or cash dragged out of better-yielding deposits.

Every privately rented home in England and Wales must reach EPC band C by 1 October 2030. Spend from 1 October 2025 counts toward a £10,000-per-property cost cap.

Fifteen thousand pounds covers a typical D-to-C upgrade with room to spare — loft and cavity-wall insulation, a new boiler, double glazing, or a solid chunk toward a heat pump.

Eligible spend includes:

• Solar panels
• Loft, cavity-wall, pipe and boiler insulation
• Air or ground source heat pumps
• Boiler upgrades and replacement windows
• EV charging points, rainwater harvesting and small wind turbines

To qualify, you must:

• Already hold a TMW buy-to-let mortgage
• Have owned and let the property for at least six months
• Have made full payments for six months, with no arrears in the last 12
• Have no more than two people on the mortgage
• Not be mid product-switch, and not let to an immediate family member

There is no Decision in Principle. TMW decides after a valuation and credit search, and offers stay open for six months.

TMW is funding free retrofit assessments through Eco Approach for landlords with properties rated D to G. If you don't yet know your number, that assessment is the cheapest place to start — it shows how far the property sits from EPC C and estimates the cost.

My honest view: this is secured debt that raises your mortgage balance, not free money. But for an existing TMW landlord facing EPC C by 2030, it is the cheapest, lowest-friction funding I have seen. If you were going to insulate, re-glaze or replace a boiler anyway, locking 2.99% beats almost any alternative.

If that is you, talk to your mortgage adviser about this option. TMW call it the "Energy Efficiency Further Advance mortgage"

Source:

- https://cyborg.finance/news/tmw-energy-efficency-further-advance