Exposed wet rot decaying timbers behind a bath tub in a bathroom

Should I Replace Rotten Timber in My Bathroom?

17 October 2023

The bathroom is a space where many will encounter problems like damp, black mould, and dry rot, because it’s a space where plenty of moisture is often created.

The issue is that people often don’t understand the issue at hand in their bathroom, and either replace their rotten timber before they should do, without having solved the initial problem that led to the rot growing.

So, if you own a bathroom that is playing host to some rotten timber, when should that timber be replaced, and what steps do you need to take to make sure that the rot doesn’t come back?

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Why Does Rot Appear in Bathroom Timber?

Closeup of dry rot fruiting body

Rot is a problem which appears thanks to the abundance of one simple factor: moisture.

It really doesn’t matter in what way the moisture is building up in your bathroom. It could be that humid air isn’t being ventilated from the room correctly, and that the gradual buildup of this humidity in the bathroom is leading to condensation based damp.

It could also be that a leaky pipe or drain is causing a lot of water to consistently pool or collect around timber in your bathroom, or it could be as simple as someone sloshing water everywhere when they are getting out of the bath or shower.

The crux of the matter is that this moisture will be what allows the wet or dry rot fungus to grow.

Let’s say that a leaky pipe has been spewing beneath a floorboard for a long time. This leak has caused what appears to be rising damp to appear in your bathroom’s walls, and now you have noticed that the skirting boards you have in the bathroom connected to these damp walls are displaying signs of being rotten.

That’s happened because the damp in the wall has transferred into the timber, and when that timber takes on an excessive moisture content it becomes the perfect sport for rot fungus to grow.

The differences between wet and dry rot can be read about here, but simply put the rot is a living fungus which feeds on the moisture within the timber, leaving it brittle, dry, and compromised by the time its done.

So, if you believe that your bathroom has rotten timber, its important to put a stop to its spread, but where should you begin?

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What Do I Need to do Before Replacing my Rotten Timber?

Wet rot damage on window frame

Before you set about replacing the rotten timber in your bathroom, or looking into a professional to restore the quality of the timber in your property to a decent state, there are a few things you need to do.

First, you need to make sure that the source of the water that was feeding the fungus in your rotten timber has been dealt with. This might mean that you install additional ventilation options in your bathroom, or that you have certain pipes replaced, or just tighten the seals on pipes if that solves the leak.

The point is, you need to be sure that whatever caused the timber to go rotten in the first place has been dealt with.

Forgoing this step only means that you will be right back where you started in the coming weeks or months because the replacement timber is only going to take on that same water, and play host to a fresh infestation of wet or dry rot.

How can we be sure that the rot will come back?

Because wet rot, dry rot, and black mould are all types of fungus, with one of their key attributes being that the fruiting body of this fungus will release tiny spores into the air so that it can reproduce. It’s a compounding problem, the more spores that grow into a Sporophore (the fruiting body), the more spores that the fungus can release, and so on.

With all that in mind, remember that these tiny spores are carried on air currents, so even if the spores aren’t present in your bathroom anymore there is every chance some could be blown in and land on that fresh timber, and start to grow if it has been exposed to an abundance of moisture.

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Should I Replace My Rotten Timber?

Closeup of wet rot decay and damage to a skirting board within a property

There are a few potential answers to this question, and they depend on your expertise level when it comes to timber repair and replacement, as well as the amount of timber that has been affected by the rot itself.

So, let’s assume that it’s a small amount of timber that has been affected by the rot. Perhaps a lining board beneath a bath or a shower, a shelf, a cupboard door; something small or simple to handle. In this instance, if you feel comfortable doing so, you can of course replace the timber (provided that the source of the rot has been dealt with).

This would usually fall under the remit of DIY, and can be accomplished by those willing to spend the time on it.

What might be more complicated is if the rot has spread to other timber. For example, if it has managed to ruin your floorboards, structural timber, or even wreak havoc on fixtures like cabinets, bath and shower fittings, or just fitted elements in the bathroom.

This might fall beyond the remit of DIY.

Let’s take the example of the floorboards being rotten. Let’s say that the water pipe under the floorboards connected to the bath has been leaking, and now you have a nasty damp problem which has led to your floorboards becoming rotten.

This is, as you might have guessed, is a bigger problem than condensation ruining a cabinet door. Obviously, if you have experience in carpentry, timber care, or damp proofing, then by all means go ahead and attempt to solve the problem if you feel comfortable, but for lasting and effective results we would recommend having a professional solution.

Looking to an accredited member of the PCA is potentially the best course of action in this situation. A properly qualified member of the PCA can inspect your bathroom to fully understand the extent of the damage the rot has caused, and establish what the cause was – as well as the best way to put a stop to it.

Once the survey has been completed, you should be presented with a full report detailing how the infested timber will be repaired or replaced, with the work undertaken by technicians skilled in carpentry and timber care.

This professional route isn’t just the best option for a lasting solution – it will keep you protected too. All timber treatments completed by Timberwise come with a 20 year guarantee on the work done, meaning that if the rot does return after the timber has been treated then our team will help fix the problem, giving you peace of mind that your property is protected.

If you are concerned about rot in your bathroom, and you need professional help to put a stop to its spread, then you should talk to our team today.

You can arrange a survey via the form below, or call 0800 288 8660 to speak to our team directly.