A rental property with a cold loft, ageing boiler and high electricity use can become expensive for both landlord and tenant very quickly. This landlord retrofit example shows how a planned upgrade can improve comfort, lower running costs and create a more attractive, future-ready home without replacing everything at once.
The property: a typical inefficient rental home
Consider a three-bedroom 1930s semi-detached house in Leicester. The landlord owns the property as a long-term investment and has reliable tenants, but the house has an EPC rating of D, a gas boiler nearing the end of its working life, minimal loft insulation and single-glazed windows in a rear extension.
The tenants are reporting cold bedrooms in winter and high electricity bills. The landlord is also concerned that future energy-efficiency requirements may make the property harder or more costly to let if improvements are delayed. They do not want a disruptive refurbishment, and they need each pound spent to add genuine value.
This is the point where a whole-property approach matters. Fitting a heat pump before reducing heat loss, for example, may mean selecting a larger system than necessary. Installing solar panels without considering daytime electricity use or battery storage can also limit the value of the generation. The most effective retrofit starts with the fabric of the building, then designs low-carbon systems around it.
Landlord retrofit example: the staged improvement plan
The landlord commissions an assessment of the property, looking at insulation levels, ventilation, existing heating, hot-water demand, roof suitability and electrical capacity. The resulting plan is completed in stages between tenancies where possible, with the main works carefully scheduled to minimise disruption.
Step one: reduce heat loss first
The first work is straightforward but significant. The loft insulation is increased to current recommended levels, draughts around doors and service penetrations are addressed, and the single-glazed extension windows are replaced with efficient double glazing. The landlord also installs better heating controls, including a programmable thermostat and thermostatic radiator valves where suitable.
These measures do not have the same visual impact as a new kitchen, but they make the home easier and cheaper to heat. They also allow the future heating system to operate at lower flow temperatures, which is particularly valuable for an air source heat pump.
Insulation must be balanced with ventilation. A tighter home needs a reliable route for fresh air and moisture control, especially in kitchens, bathrooms and bedrooms. In some properties, improved extractor fans may be enough. In others, mechanical ventilation with heat recovery, known as MVHR, can provide controlled ventilation while retaining heat that would otherwise be lost. The right choice depends on the building layout, airtightness and budget.
Step two: replace the ageing boiler with efficient heating
Once the house is retaining heat more effectively, the landlord replaces the old gas boiler with an air source heat pump and a properly sized hot-water cylinder. Some radiators are upgraded so they can deliver the required warmth at lower temperatures, while others remain suitable after the heat-loss calculation.
This is not a like-for-like boiler swap. Heat pumps work differently and perform best when the system has been designed correctly. The installer considers room-by-room heat loss, radiator output, cylinder space, outdoor unit location and the property’s electrical supply. Good controls are equally important, giving tenants a simple way to keep the home comfortable rather than constantly switching the heating on and off.
For a landlord, the benefits are practical. The property moves away from direct reliance on fossil-fuel heating, tenants gain steadier indoor temperatures, and the new system can support a stronger EPC position. Actual savings will depend on the tenants’ heating habits, electricity tariff, insulation standard and the performance of the old boiler, so a credible proposal should avoid promising one fixed figure for every home.
Step three: add solar panels and battery storage
The south-west-facing roof provides space for a solar PV system. The landlord chooses a system sized around the property’s annual electricity use and roof capacity, rather than simply filling every available section of roof. Solar panels help generate electricity during daylight hours for appliances, lighting and the heat pump.
A solar battery is included because the tenants are often out during the middle of the day. Instead of exporting all surplus generation immediately, more solar electricity can be stored for use in the evening. This can improve self-consumption and reduce the amount of electricity bought from the grid at higher-cost times.
Battery storage is not essential for every rental property. A smaller budget, limited electricity use or tenants who are home during the day may make solar alone the better first step. However, where a heat pump, electric cooking, home working or future EV charging are likely, battery storage can make the system more flexible.
Step four: prepare for future tenant needs
The landlord also has the consumer unit checked and allows capacity for an EV charger. They decide not to install a charger immediately because there is no off-street parking arrangement for the current tenancy. However, planning for it during electrical works avoids unnecessary repeat disruption later.
This is a useful lesson for landlords with several properties. A retrofit should meet today’s needs while leaving sensible options open. It is often cheaper to plan cable routes, electrical upgrades and equipment locations once than to revisit the same work in a few years.
What changes after the retrofit?
The completed home is warmer, easier to control and less exposed to rising gas costs. The tenants notice fewer cold spots, more consistent hot water and lower reliance on grid electricity when the solar system is producing. The landlord has a better-quality asset that is more appealing to tenants who care about comfort and energy bills.
The value is not limited to monthly energy use. New systems can reduce maintenance uncertainty associated with an ageing boiler, while improved insulation helps protect the building from condensation risks caused by cold internal surfaces. A well-presented, energy-efficient property may also support longer tenancies and reduce void periods, although this will vary by location and local rental demand.
The landlord keeps records of the installation, warranties, commissioning information and tenant guidance. This matters. A high-quality system can still disappoint if tenants do not understand how to use the controls, when solar generation is highest, or why a heat pump is designed to provide steady background warmth.
Budgeting and choosing the right order of work
Every landlord retrofit has trade-offs. A full upgrade may be the most efficient long-term route, but it is not always practical to complete in one phase. Roof condition, available capital, tenant access and the expected life of existing equipment all affect the programme.
If the boiler has failed and the property is poorly insulated, emergency replacement may be unavoidable. If the boiler is still dependable, starting with insulation, ventilation and controls can be a sensible first investment. If the roof needs replacing soon, in-roof solar can be worth considering as part of that project rather than fitting conventional panels first and changing the roof later.
Landlords should also consider available grants, tax treatment and financing carefully, as eligibility and rules can change. An MCS-certified installation is particularly important where relevant support schemes or export arrangements require it, as well as for confidence in system design and installation standards.
A practical route to a stronger rental property
The best landlord retrofit is rarely the one with the longest equipment list. It is the one that solves the property’s biggest weaknesses in the right order, matches the landlord’s budget and gives tenants a home they can afford to live in comfortably.
For landlords in Leicester and across the UK, Airtech Renewables can help assess how solar, battery storage, heat pumps, ventilation and efficient heating controls could work together in a rental property. Start with the building, plan around real energy use, and invest in improvements that continue to make sense long after the next tenancy begins.