June 27, 2025
Planning a home renovation or extension can be exciting, but even the most organised budgets can be blindsided by hidden or overlooked costs. While materials and labour are front of mind, there are several common extras that often catch homeowners off guard. Budgeting for these from the start can save you a lot of stress—and money, down the line.
Even minor renovations can uncover structural issues beneath floors or behind walls. Water damage, pest infestations, and foundation weaknesses are all problems that can derail your timeline and budget. For example, water damage repairs may cost a few thousand pounds, but serious foundation issues could escalate beyond £20,000. Always schedule a pre-project inspection with a surveyor or structural engineer to reduce the likelihood of surprise repairs.
Permit fees are essential but frequently forgotten. Whether you’re remodelling a bathroom or building an extension, local authorities may require approval. Costs can range from £150 to over £1,000 depending on the work. Failing to get the right permits could lead to fines or delays, especially during inspections. To stay on track, research permit requirements early and build this into your project timeline.
If your kitchen, bathroom, or entire home is out of action, alternative arrangements will be necessary. Eating out or ordering takeaway during a kitchen renovation can add hundreds of pounds to your budget, while temporary housing for larger works could exceed £2,000 a month. Consider completing works in phases or arranging to stay with friends or family to reduce costs.
It’s standard practice to order more materials than needed to account for breakages and cuts, typically 10-15% extra. However, changes mid-project—such as switching tiles or moving walls—can cause delays and significant budget increases. To manage this, finalise your designs in advance and build a 10-20% contingency into your budget for adjustments.
Modernising an older home often means updating plumbing or electrics. Full rewires and plumbing upgrades can each cost thousands. Labour costs may also rise if the team discovers asbestos, rotten joists, or other issues that require specialist work. A full home assessment before starting work will help flag these risks and give you a clearer idea of potential extra costs.
Removing debris, old fittings, and unused materials takes more than a broom. Skip hire and specialist waste disposal can add £150–£300 per week to your budget, and more for hazardous materials. After the work is done, don’t forget the final clean. Professional post-build cleaning can cost £200–£500 and ensures your new space is move-in ready.
Working with a designer or architect can hugely improve your outcome but comes at a price. Basic consultations may start at £50 per hour, while full design packages can be in the thousands. After the dust settles, budget for repainting, touching up scuffed surfaces, or replacing furnishings affected during the renovation.
Storing furniture or belongings off-site may be necessary for space or protection. Monthly storage units typically range from £50 to £200. If you live in a managed development or block, check for HOA (Homeowners Association) rules—these can include additional fees or restrictions that could affect your project.
Renovating often means increasing the value of your home, and that can affect your insurance. Speak to your provider before starting work to see if you need additional protection during the build or to update your policy post-completion. Uninsured improvements can leave you exposed if something goes wrong.
MKW Builders offers transparent pricing, reliable timelines, and expert support to help you stay in control of your renovation budget. Call us on 01204358908 or fill out our contact form to get started with your next project.
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