Homeowner Advice

General tips and advice for homeowners covering maintenance, seasonal tips and everyday property care.

Focus on Damp Part Three: Penetrating Damp

29th November 2019

Damp is a nightmare for most homeowners. Not only is it unsightly and inconvenient, there is that deep fear that it is also going to cost a fortune to fix. There are three main types of damp; over the last couple of weeks we have already looked at rising damp and condensation. This week, we are focusing on penetrating damp; what it is, and how you can fix it.

What is penetrating damp?

While rising damp is water soaking up from the ground, and condensation is water from the air in the house collecting on cold walls and windows, penetrating damp is caused by water getting into your house from the outside. Usually, penetrating damp is a sign that there is a structural problem with your home; anything from a broken gutter or missing tile, to more serious roofing and rendering problems.

Identifying penetrating damp

If you notice damp patches on walls, ceilings and floors that aren’t mouldy, and which don’t meet the ground, it is most likely to be penetrating damp. Sometimes, the patches can grow bigger or darker when it rains – this is a clear sign that, somehow, water is finding its way into your home.

Dealing with penetrating damp

Penetrating damp isn’t necessarily a serious problem, but like many home maintenance issues, the longer you take to deal with it, the more the problem will grow. If left unchecked, penetrating damp can cause serious structural problems, which could be time consuming and expensive to fix (not to mention messy). So, don’t put it off – if you notice damp, get in touch with a damp specialist who will advise you on the best cause of action.

The first thing that you need to do is identify the cause of the damp. If it is the roof or ceiling, pop outside and see if you can see anything amiss on the roof. If it is high up in a wall, check out the guttering. Does it get worse when it rains? These are all hints that will help a damp specialist or builder to pinpoint the spot where the water is coming in.

Once you have identified the source of the leak, you need to find out how to fix it. Your damp specialist may well recommend a builder or roofer to look at the problem; if this is the case, it is a good idea to go with the recommended tradesperson, but to get a few quotes, too, so that you have an idea of the costs involved.

Once the repairs have been done, you should be drip and damp patch free! You may need a dehumidifier to completely dry out the plaster, after which you can decorate over the patch; you’ll never know it was there!

We hope that you stay damp free this autumn and winter, but if you would like more advice, just follow us on Facebook or Twitter, or Ask A Trader.

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Find clear, practical answers to common homeowner advice questions, helping homeowners understand everyday issues, know what checks they can carry out safely, and when it is best to contact a qualified professional.

What home repairs should I never attempt myself?

Gas work - full stop. Any work on gas appliances must be done by a Gas Safe registered engineer by law. Structural changes like removing walls, altering roof timbers, or touching anything load-bearing need professional assessment and often Building Regulations sign-off. Electrical work involving the consumer unit or new circuits must meet Part P. And if your property was built before 2000, be aware asbestos may be present - it can only be handled by a licensed specialist.
Which home improvements add the most value to a property?

Improvements that add usable space or modernise the rooms buyers scrutinise most tend to deliver the strongest returns. Loft conversions consistently top the list - adding a bedroom and bathroom can add more value than the work costs in many areas. Kitchen and bathroom updates are next. Open-plan ground-floor extensions connecting to a kitchen-diner have become one of the most sought-after layouts in UK family homes. And energy improvements - insulation, a new boiler, solar panels - are increasingly influencing buyer decisions as running costs become a bigger part of the conversation.
Should I renovate my home or move house?

There's no universal right answer - it depends on your situation. Moving gets you what you want without living through a building site, but stamp duty, estate agent fees, and moving costs can easily add up to tens of thousands of pounds. Renovating lets you stay put and invest in your own property, but comes with disruption and unexpected costs. The most useful comparison: get a clear view of what your home could realistically be worth after the work, and what a move would actually cost end to end. A local estate agent and a builder's quote can give you those two numbers.
What does a home survey actually cover and do I need one when buying?

A survey is an independent assessment of a property's condition carried out by a qualified surveyor - separate from the mortgage valuation, which only tells the lender what the property is worth, not what's wrong with it. A HomeBuyer Report flags visible defects and anything that needs further investigation. A Full Building Survey goes deeper and is worth the extra cost on older, larger, or unusual properties. Given that a house is likely the biggest purchase you'll ever make, skipping the survey to save a few hundred pounds is a false economy - a single missed issue can cost far more to put right.
What should I do before starting any major home improvement project?

Get your paperwork in order before anyone picks up a tool. Check whether you need planning permission or Building Regulations approval. Find out whether a Party Wall Agreement applies. Confirm your home insurance covers you during the works. Get at least three written quotes and make sure the scope of work is clearly agreed in writing with whoever you hire. And have a contingency budget - on almost any renovation, something unexpected comes up. The projects that go smoothly are usually the ones that were properly planned before they started.
What is the difference between freehold and leasehold and why does it matter for home improvements?

If you own the freehold, you own the property and the land it sits on outright - you can generally do what you like subject to planning rules. If you own a leasehold property (common with flats), you own the right to live there for the remaining lease term, but the freeholder owns the building. This matters for home improvements because many leases require you to get the freeholder's written permission before making alterations - sometimes even internal ones. Always check your lease before starting any work, as doing alterations without the required consent can cause problems when you come to sell.

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