Extensions Cost
Estimate home extension, single-storey extension, double-storey extension, loft conversion, garage conversion, basement conversion and extension cost per m².
View extension calculators
Cost calculator directory
Home Improvement Cost Calculators UK
Find the right UK home improvement cost calculator for your project. CostIntel covers extensions, roofing, driveways, landscaping, windows, doors, heating, electrical work, plumbing, interiors and project planning tools.
Browse cost calculator categories
Start with the category that matches your project. Each section includes calculators for different project types, materials, specifications and quote-checking situations.
Roofing Cost
Estimate roof replacement, roof repair, flat roof replacement, tiled roof replacement, slate roof replacement and roof cost per m².
View roofing calculatorsDriveway Cost
Compare driveway costs for resin, tarmac, block paving, concrete, excavation and cost per m² quote checking.
View driveway calculatorsLandscaping Cost
Estimate garden landscaping, patios, decking, fencing, turf installation, artificial grass, retaining walls and garden drainage.
View landscaping calculatorsWindows & Doors Cost
Estimate window replacement, double glazing, front doors, patio doors and bifold doors based on size, specification and installation.
View windows and doors calculatorsEnergy & Heating Cost
Estimate boiler installation, heat pumps, solar panels, solar batteries, insulation and EPC improvement costs.
View energy and heating calculatorsElectrical Cost
Estimate rewiring, EV charger installation and consumer unit replacement costs for UK homes.
View electrical calculatorsPlumbing & Drainage Cost
Estimate drainage installation, septic tank costs, bathroom plumbing and kitchen plumbing work.
View plumbing calculatorsInterior Cost
Estimate kitchen renovation, bathroom renovation, flooring, carpet installation, plastering, painting and flooring cost per m².
View interior calculatorsProject Planning Tools
Plan renovation budgets, compare build versus buy decisions, estimate renovation ROI and check possible property value uplift.
View planning toolsPopular home improvement calculators
These calculators are useful starting points for common UK renovation and home improvement projects.
Home Extension Cost Calculator
Estimate a broad home extension budget before comparing more specific extension types.
Estimate home extension costRoof Replacement Cost Calculator
Check a roof replacement estimate using roof type, size, access and specification.
Estimate roof replacement costDriveway Cost Calculator
Compare driveway costs across common surface types and preparation levels.
Estimate driveway costKitchen Renovation Cost Calculator
Plan a kitchen renovation budget around size, finish level and fitting complexity.
Estimate kitchen renovation costBathroom Renovation Cost Calculator
Estimate bathroom renovation costs using project scope, fittings and finish level.
Estimate bathroom renovation costWindow Replacement Cost Calculator
Estimate replacement window costs by number of units, size, frame and glazing type.
Estimate window replacement costBoiler Installation Cost Calculator
Estimate boiler installation costs based on property needs and installation scope.
Estimate boiler installation costRewiring Cost Calculator
Estimate rewiring costs for UK homes based on property size and electrical scope.
Estimate rewiring costChoose a calculator based on where you are in the project
The right calculator depends on whether you are setting a first budget, comparing options or checking a quote.
I am setting an early budget
Start with the main category hub for your project. It will show the calculators available and explain which cost drivers matter most.
I already know the project type
Use the specific calculator for the job, such as a roof replacement, window replacement, boiler installation or kitchen renovation calculator.
I am comparing materials or specifications
Use the material-specific calculators where available, such as resin driveway, tarmac driveway, block paving, flat roof, tiled roof or slate roof calculators.
I have a quote and want to check it
Use cost per m² calculators and project-specific tools to check whether the quote seems aligned with the scope, material and preparation work.
Driveway cost per m² · Roof cost per m² · Extension cost per m²
Full CostIntel calculator directory
Use this directory to jump straight to a specific calculator.
What CostIntel calculators estimate
CostIntel calculators estimate planning ranges using the main cost drivers for each project type. These may include area, size, material, labour, specification, access, preparation, region and contingency.
Labour
Labour is often one of the largest parts of a home improvement quote. The calculators consider project type, complexity and fitting time where relevant.
Materials
Material choice can change the estimate significantly. A uPVC window, aluminium bifold door, resin driveway or slate roof will each have different cost patterns.
Site conditions
Access, preparation, removal, disposal, ground conditions and finishing work can explain why two similar projects receive different quotes.
Region
UK labour and project costs vary by area. Regional adjustment helps avoid treating every quote as if it came from the same market.
Using calculators to check quotes
A cost calculator is most useful when the project scope is clear. Before comparing an estimate with a contractor quote, check what the quote includes: labour, materials, removal, disposal, VAT, preparation, finishing work and any assumptions.
A cheaper quote is not always better if it leaves out work that another contractor included. A higher quote may be reasonable if it includes access equipment, structural preparation, better materials or more detailed finishing.
How CostIntel calculates home improvement costs
CostIntel calculators are built around project scope, materials, labour, site conditions and regional variation. The aim is to give homeowners a clearer planning range before comparing quotes or setting a renovation budget.
For more detail, read our methodology, pricing data and how costs are calculated pages.
Learn more about project costs
If you want more context before using a calculator, read the cost guides for common project types. These explain the main cost drivers, typical quote differences and planning considerations.
Cost Guides
Browse the full guide section for plain-English explanations of UK home improvement costs.
View cost guidesExtension Cost Guide
Read about extension cost drivers, project size, build type and common budget considerations.
Read extension cost guideRoofing Cost Guide
Understand how roof type, access, materials and repair scope can affect roofing quotes.
Read roofing cost guideDriveway Cost Guide
Compare driveway materials, preparation, excavation and quote differences before estimating.
Read driveway cost guideCost calculator FAQs
What are CostIntel calculators for?
CostIntel calculators are designed to give UK homeowners planning estimates for home improvement projects. They help with early budgeting, quote checking and comparing project options.
Are CostIntel estimates fixed quotes?
No. The calculators provide planning estimates based on typical cost drivers. A contractor needs to inspect the property and confirm the scope before giving a fixed quote.
Which calculator should I use first?
Start with the category that matches your project. If you are planning an extension, use the extensions cost section. If you are replacing windows or doors, use the windows and doors section.
Can I use these calculators to check a quote?
Yes, but only as a planning check. Make sure the quote scope is clear before comparing it with a calculator estimate. Labour, materials, removal, finishing work, VAT and access can all affect the price.
Why do home improvement quotes vary so much?
Quotes vary because projects differ in size, materials, labour, access, preparation, region and finishing detail. Two quotes may also include different levels of work.
Do the calculators include labour and materials?
Most CostIntel calculators are designed around total project cost drivers, including labour and materials where relevant. Each calculator should be read in line with its own assumptions.
Are the calculators only for UK projects?
Yes. CostIntel is built for UK home improvement cost planning, using UK-style project scopes, terminology and cost assumptions.
How often should cost estimates be reviewed?
Costs can change as labour rates, material prices and demand shift. Use the calculators as planning tools and compare them with current local quotes before making decisions.