FREE INTERACTIVE TOOL · WHOLE-HOME PLANNING

Home modification cost estimator

Accessible Home Hub editorial · Published 30 October 2026

Build a phased budget for entrances, bathrooms, kitchens and other home adaptations using your own local allowances. Keep unpriced work visible and take the breakdown to your next conversation.

Resident preparing vegetables at a comfortable kitchen work surface with everyday items within reach.
Illustrative setting; individual needs and installation requirements vary.

Choose work and enter complete-scope allowances

Enter a total allowance for each selected row, including the materials, installation and taxes you intend it to cover. Leave both amounts blank when the item is not yet priced. Use zero only when you have deliberately allowed no additional cost, for example because it is included elsewhere.

Assign shared work and professional fees once. First and later phases are your planning labels, not a clinical priority or a construction schedule. Use the detailed bathroom estimator when you need to build that room’s subtotal first.

Changing currency clears all money amounts. It does not convert them; scope notes and phase choices remain.

Choose your own allowance for uncertainty. No percentage is recommended for every project. This is separate from unpriced work.

Select a row to open its amounts, phase and scope note. Both amounts accept up to two decimal places.

Include the complete approach, landings, site preparation, drainage and making good.

Include the agreed openings, hardware, structural checks and finishes.

Use one complete bathroom allowance, or bring over an itemised subtotal. Do not count the same work in both tools.

Include worktop, storage, sink, service changes and installation in the agreed scope.

Budget the chosen lift or stairlift option, surveys, building work, power, landings and aftercare separately where needed.

Include preparation, removal, thresholds and the complete installed area.

Include installation, required professional work, setup and backup arrangements.

Include only fees not already contained in another selected allowance.

Enter the applicable fees only after checking the local project requirements.

Allow for agreed temporary facilities, accommodation or access arrangements where needed.

Describe what this covers. Include shared preparation, disposal or making good once, rather than duplicating a bundled quote.

Understand the calculation and the gaps

  1. Sum the entered lower allowances for each phase. Repeat for the upper allowances.
  2. Multiply each phase’s subtotal by your contingency percentage and round to cents.
  3. Add the contingency to each phase, then add the two phases for the combined priced portion.

With the worked example: first-phase allowances of 200–400 and 300–500 produce 500–900 before contingency. A later-phase allowance of 5,000–8,000 brings the combined subtotal to 5,500–8,900. At 10%, the combined priced portion is 6,050–9,790 in the chosen currency. These numbers demonstrate arithmetic only.

Check the complete written scope

Ask what covers site preparation, installation, professional fees, permissions, service changes, disposal, finishes, taxes and aftercare. The tool cannot detect the same work in two allowances. Keep running maintenance costs separate from one-off work, or describe their time period explicitly.

Unknown is different from zero

Unpriced selected work appears in the result and CSV but adds no amount to the totals. A contingency percentage does not price that missing work. If nothing is priced, the tool shows “not calculated” rather than a free project.

Currency is a label, not conversion

Use consistent local amounts in USD, GBP, CAD or AUD. Changing currency clears the numeric allowances. Confirm taxes and any supplier relief before relying on a payable price.

Keep funding decisions separate

Use the guided funding finder and country resources alongside this record. The estimator does not subtract an expected grant, reimbursement or tax saving, and it does not determine affordability or borrowing.

Prepare the next discussion

Compare complete quote scopesOpen the free planning packFind professional resourcesReview room-by-room tasks

Sources and method

The arithmetic, phase labels and worked example are original planning aids. They are not a price survey or assessed adaptation plan.

Source guidance checked 30 October 2026. These are jurisdiction-labelled consumer resources, not worldwide contract rules. Check requirements for the actual project locally.

Frequently asked questions

How much will my home modifications cost?

This tool totals your entered local allowances; it does not supply market prices. Build a consistent scope, include professional and shared project costs once, and replace assumptions with comparable written quotes. The result is a planning range, not a quotation.

Does changing the budget currency convert my amounts?

No. Changing currency clears the numeric allowances so you can enter local figures in USD, GBP, CAD or AUD. It does not use an exchange rate. Scope notes and phase choices remain for you to review.

Are grants, tax credits or insurance deducted from the estimate?

No. Funding and tax decisions need separate checks with the responsible organisation. Keep the full project scope and costs visible, then use the funding finder and country guides to prepare the payment and approval questions.

What happens to work that is not yet priced?

Leave both amounts blank for that selected row. It remains in the scope and export but is excluded from the totals, which are labelled partial. Contingency does not replace the missing price. If no selected item is priced, the tool shows that a cost has not been calculated.

Accessible Home Hub · accessiblehomehub.com · Planning information; confirm individual needs and local requirements.

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