How estimates work

RangVault turns the measurements and product figures you enter into a planning estimate. The results are starting points for a conversation with a painter or supplier. Check the product pack and measure your actual space before buying.

Paintable walls and paint

For each rectangular room, gross wall area in square feet is 2 × (length + width) × height. We subtract the total area of doors and windows you enter. Each additional room is calculated separately and added to the estimate. Openings must be smaller than that room's gross wall area. If you select a ceiling, its area is length × width for each room; it is then added to the paintable area.

Area across coats is the combined paintable area multiplied by your chosen number of coats. Estimated paint litres are rounded up from (area across coats ÷ coverage in sq ft per litre) × 1.10. The extra 10% is a planning allowance, not a promise that it will cover every loss. The illustrative range applies the same formula using 120 and 90 sq ft per litre per coat. The single estimate uses the coverage you enter; always follow your paint tin's instructions. Recommended tins are selected from 1 L, 4 L, 10 L and 20 L to cover the calculated litres; leftover equals purchased litres minus calculated litres.

Primer, putty and painting cost

Primer and wall putty are optional and off by default. When enabled, primer quantity in litres is rounded up from (paintable area ÷ your primer coverage) × 1.10. Putty quantity in kilograms uses the same calculation with wall area after openings ÷ your putty coverage, so it excludes the ceiling. These quantities use one application pass; ask your painter and check the product instructions if more coats are required. Paint cost is purchased tin litres × your paint price per litre + primer litres × primer price + putty kilograms × putty price. Estimated labour is paintable area × your painter rate per sq ft. The displayed total combines materials and labour. Default prices are examples to show the tool working, not market quotations. Repair, preparation, taxes, delivery and other supplies are excluded.

Tiles and flooring

Floor area is length × width in square feet. The tool increases it by the extra percentage you enter for cutting, then divides by the square feet covered per box and rounds up to a full box. Estimated material cost is boxes × your price per box. Measure unusual floor shapes separately and confirm the box's stated usable coverage and your installer's waste allowance.

Furniture fit

The furniture tool checks the length and width you enter against the room in its measured orientation and turned 90 degrees. It chooses the orientation with more usable space, and marks a comfortable fit only when at least twice your requested clearance remains in both directions. A footprint check cannot account for doors opening, cupboards, uneven walls, delivery routes or movement around furniture; measure these on site.

Lighting and budget

The lighting planner converts floor area from square feet to square metres using 0.09290304, multiplies by your target lux to estimate total lumens, then divides by the lumens per fixture and rounds up. It is a starting estimate for ambient light, not an electrical plan. Room height, daylight, fixture beam spread and finishes also matter. The budget planner adds the prices you enter for paint, floor, furniture, lighting, labour and other costs; it then applies your chosen percentage buffer to that subtotal. It does not fetch prices or guarantee a final quote.

Ready to try your own figures? Open the paint calculator, tile calculator, furniture fit checker, lighting planner or room budget planner.