Accurately measuring your room ensures optimal performance and a perfect fit for your underfloor heating system.

Follow these three straightforward steps:

Step 1: Determine the Total Room Area
- Measure the Length (L) and Width (W) of the room in meters.

Calculate the total room size using the formula:
Total Room Area = L × W

Step 2: Subtract Fixed Furniture or Fittings
- Measure and total the area of any immovable fixtures—such as built-in cabinets, kitchen islands, bathroom suites (e.g., shower trays, baths, toilets, sinks), or other permanent items. Let’s call this F (total fixed area in square meters).

Apply the formula:
Fixed Area (F) = Sum of all L × W of fixed items

Step 3: Calculate the Heatable Floor Area
- Deduct the fixed area (F) from the total room area to find the usable, heatable floor space.

Use this formula:
Heatable Area = Total Room Area − Fixed Area

Additional Guidance for Installers and Homeowners

Perimeter & Mat Spacing Allowance:
For electric mat systems, it's standard practice to reduce the heatable area by 10%. This accounts for spacing around the room’s perimeter (typically 50–100 mm) and ensures mats don’t overlap.

Choosing Loose Cable in Irregular Spaces
In rooms with awkward shapes—like bathrooms or annexes—a loose cable system from MaxHeatUFH is the best choice. This flexible solution provides maximum coverage, even heat distribution, and a simpler installation.

System Sizing for Lifetime Warranty
Remember, once installed, your heating element cannot be cut—doing so will void your lifetime warranty. Make sure to order the correct size from the outset.

Summary of Formulas

Total Room Area: Total Room Area = L × W
Fixed Area (sum of fitments): Fixed Area = Σ (L × W)
Heatable Floor Area: Heatable Area = Total Room Area − Fixed Area

Alternatively, click the 'Contact Us' button below, complete the quote request form, and one of our underfloor heating experts will be able to calculate all of this information for you, provide you with a design off the floorplans provided, and also a quotation for the supply of the full system, saving you both time and money.