Home Insurance Sum Insured Calculator

How this sum-insured guide is calculated

Buildings insurance should cover the cost to demolish and rebuild your home from scratch — including materials and labour — not what it would sell for on the open market; in many areas these two figures are very different because land makes up a large share of a home's sale price. This calculator estimates a rebuild sum by multiplying your internal floor area by a rebuild rate per square metre (defaulting to a broadly representative £2,000/m², which you can override with a more accurate regional or RICS/BCIS figure) and a house-type adjustment — detached homes have proportionally more external wall per square metre of floor space, so they cost more per m² to rebuild, while flats share structure with neighbouring units and sit at the other end of the scale. Contents insurance is estimated using a simple £15,000-per-bedroom baseline, a rule of thumb used by several UK insurers' own online tools, plus any high-value items add-on you enter for valuables like jewellery or electronics that push you above the baseline or a typical single-article limit. Getting the sum insured right matters: under-insuring buildings can trigger an "average" clause that cuts a claim payout proportionally, and under-insuring contents means a big loss might not be fully covered — so treat these figures as a starting point and get a proper valuation if you're unsure.