Why is my bungalow so cold?

What this usually means

A building loses heat through its external surfaces — roof, walls, floor and windows — roughly in proportion to their area, so a home's shape strongly affects how much heat it loses for a given amount of living space. A two-storey house stacks its floor area, so the roof and ground floor each cover only half the footprint of the same area built as a bungalow; a bungalow spreads the whole floor area across one level, so its roof and its ground floor are about twice the area relative to the space inside. Because the roof and floor are major heat-loss paths, a bungalow inherently loses more heat through the top and bottom of the building than a house of the same size — which is the core reason it feels colder and costs more to heat.

Several related factors add to this. A bungalow also tends to have a large area of external wall wrapping its single-storey perimeter, and being low and often detached or exposed, it can be subject to more wind, increasing both heat loss and air infiltration. Older bungalows frequently have thin loft insulation, an uninsulated solid or suspended floor, and significant air leakage through the loft hatch, floor and junctions — so the inherent shape disadvantage is compounded by under-insulation of exactly the elements (roof and floor) that matter most. The combination explains why a bungalow can feel persistently cold and be expensive to run even with the heating working hard.

Encouragingly, the bungalow's shape that causes the problem also makes the solution accessible. Because the roof and floor are the dominant losses and are usually the easiest elements to improve — a loft is readily insulated and air-sealed, and a suspended floor can often be insulated from below or during refurbishment — targeting them delivers a large reduction in heat loss for relatively modest cost. Improving the loft insulation and sealing the loft hatch, insulating the floor, draught-proofing, and then addressing the walls and windows as needed, transforms a cold bungalow. An assessment that measures where the heat actually goes confirms the priorities, so the spend goes first to the roof, floor and airtightness that, in a bungalow, dominate the loss.

Common causes

Signs and symptoms

The fabric heat loss of a dwelling is the sum over its external elements of area times U-value times temperature difference, so the ratio of external surface area to enclosed volume — and the distribution of that area — governs how much heat a home loses per unit of living space. A single-storey building has a high proportion of its surface in the roof and ground floor, because the entire floor plan is exposed at top and bottom; built as two storeys, the same floor area halves the roof and ground-floor areas relative to the space. Since roof and floor are significant loss paths, the bungalow's geometry raises its total fabric loss for the same internal area, which is the fundamental reason it is colder and costlier to heat than an equivalent house.

Infiltration and exposure act in the same direction. A low, spread-out, frequently detached building presents a large, exposed envelope and is subject to wind across its whole perimeter, increasing convective loss and driving air leakage through the loft hatch, the suspended or junctioned floor, and the many wall-roof and wall-floor junctions. Where the loft is thinly insulated and the floor uninsulated — common in older bungalows — the elements with the largest areas also have the poorest U-values, so the geometric disadvantage is compounded by the worst-performing surfaces being the most extensive ones. The result is a high heat-loss coefficient and a home that cools quickly once heating stops.

The remedy follows directly from where the area and the losses concentrate. Because the roof and floor dominate and are typically the most accessible to improve — lofts insulate and air-seal readily, and suspended floors can often be insulated from below — addressing them yields the largest reduction in heat loss for the least cost, after which the walls, windows and remaining air leakage are tackled in priority order. A measured assessment — a heat-loss calculation, thermal imaging of the cold surfaces and a blower door test of the leakage — quantifies the contribution of each element and confirms that the roof, floor and airtightness should lead the programme. This fabric-first sequence, matched to the bungalow's geometry, is what turns an inherently heat-losing shape into a genuinely warm, affordable home, rather than running the heating ever harder against the losses.

How to make a cold bungalow warm

Target the roof, floor and airtightness first — the dominant losses in a bungalow and the most treatable — then address the walls and windows, guided by a measurement of where the heat goes.

1. 01

   Measure the heat loss

   Quantify how much heat the roof, floor, walls and air leakage each lose to set priorities.

2. 02

   Insulate the loft and seal the hatch

   Improve the large roof area's insulation and air-seal the hatch, a high-value first step.

3. 03

   Insulate the floor

   Insulate the suspended or solid floor to cut the proportionally large floor loss.

4. 04

   Draught-proof the building

   Seal the air leakage at the loft, floor and junctions that a spread-out bungalow suffers.

5. 05

   Address walls and windows

   Improve the extensive walls and the windows once the roof and floor are done.

6. 06

   Verify the improvement

   Confirm the heat loss has fallen and the bungalow holds its warmth for less heating.

How to prevent it coming back

• Prioritise the roof and floor, where a bungalow loses most heat.
• Keep the loft well insulated and the hatch sealed.
• Insulate the floor and seal the junctions.
• Measure the losses to spend in the right order.