Cost of Rising Damp Treatments

Introduction to Cost of Rising Damp Treatments

We’ll also look at the various types of treatments in more detail, looking at their pros & cons and features. If you need to hire someone to treat rising damp in your home, this article will prove very useful.

Treating rising damp involves the use of materials or/and tools to fix the damage caused by rising damp and to prevent the issue recurring. It is often employed out of necessity to fix an existing problem and, importantly, stop the issue worsening! Let’s now take a look at some average costs.

How Much Does It Cost to Treat Rising Damp?

The average cost of treating rising damp will vary a lot depending on what type of treatment will be used and the extent of the problem. Damp-proof membrane costs about £100 to £150 per square metre regardless of the property.

To have a DPC injection applied to a single wall, expect to pay approximately £400 to £600 if you live in a terraced home, £700 to £800 in a semi-detached house, or £1700 to £2300 for a detached property.

If DPC injections are required for the entire house, the cost rises to around £800 to £1000 in the case of a terraced house. The price will increase to £1800 to £2400 for a semi-detached house, or £4250 to £5250 for a detached property.

Plastic DPC for one wall will cost about £200 to £400 for a terraced home, £400 to £450 for a semi-detached house, or £600 to £650 for a detached property. For an entire home, plastic DPC costs roughly £500 to £700 for a terraced house, £850 to £1000 for a semi-detached house, or £1900 to £2350 for a detached house.

Moving on to drainage channel costs, these can vary greatly depending on the extent of the work. However, in general, to have it dug along a wall without any paths or stones being laid would set you back between £180 and £220 for a terraced home. Costs would increase to £280 and £320 for a semi-detached house, or £400 to £500 for a detached house.

Should you need it dug along your whole house, it will cost about £300 to £340 for a terraced house, £500 to £600 in the case of a semi-detached house, or £1000 to £1500 for a detached home.

Whether you’d like to have a path of concrete or gravel added with the work or for paving stones to be laid, with one of these additions, the cost of having a channel dug ends up between £250 and £450 for a terraced property, £400 to £800 for a semi-detached house, or £500 to £1200 if you have a detached house.

The same type of work but where a channel is to be dug around the entire property brings the costs for a terraced, semi-detached, and detached home to about £300 to £900, £800 to £2100, and £2000 to £4000 respectively. Those costs alone emphasise just how much the price of treating rising damp can vary!

If you’d like to have cavity walls removed, it will cost about £140-£150 for one wall removal, £170 to £190 to have two removed, £190 to £220 to get rid of three, or £250 to £270 should you wish four walls to be taken down. To have anti-moisture or anti-mould paints applied to a surface will cost £25 a tub plus the labour cost.

Damp proofing specialists tend to charge between £100 and £200. How much the total labour cost will come to will depend on the extent of the work required. For instance, you might pay £200 to £300 in labour fees to have plastic DPC applied to one wall while a specialist will charge around £500 to £700 if you’d like to have a damp proof membrane fitted to one wall.

As for the supply costs, DPC injection cream costs roughly £6 for a 0.1-litre product. Plastic DPC usually costs between £0.50 and £1 per m². A damp-proof membrane, on the other hand, will cost around £1 to £5 per square metre or £1 to £3 per litre if a liquid product is used.

The overall cost of rising damp treatment will depend not only on the factors already discussed but also the size of the damp area, where you live (due to regional variations in labour rates), and ease of access.

Rising Damp Treatment Prices for Different Types of Properties:

Types of Rising Damp Treatments

As shown, there are various options when it comes to treating rising damp. In some cases, it’ll be possible to consider different choices, but in other scenarios, there may be just one suitable fix. We’ll now take a closer look at these treatments.

Damp Proof Membrane Cost

This form of DPC tends to consist of polyethylene sheets designed to stop the transmission of moisture. Their most common application is for use beneath concrete flooring to stop the floors dampening through capillary action.

A notable benefit of DPM is that it will protect concrete from any damage that could occur during building operations at a later date. However, DPM will slow the time needed for the concrete to dry out. DPM should be used if underfloor heating has been installed beneath a concrete surface.

DPM usually costs £1 to £5 per m² or £1-£3 per litre if you choose to go with a liquid DPM. Plastic DPC is a type of damp proof membrane.

Pros:

✔ Effective way to make a concrete floor damp resistant

✔ Best treatment for rising damp in a concrete floor

✔ Can protect concrete from building operations damage

✔ Perfect for a concrete floor with underfloor heating

Cons:

✖ Concrete will take longer to dry out

DPC Injection Cost

The use of DPC injection(s) is the most popular type of rising damp treatment. They are a long-term solution to rising damp and provide a rapid response to the problem.

DPC injections work by establishing a moisture-resistant barrier to halt rising damp in its tracks. This will, in turn, protect walls from damage. You can pick up a 100ml DPC injection cream for around £6.

Pros:

✔ Relatively cheap if done DIY, in terms of rising damp treatment costs

Cons:

✖ Not well suited to stone walls

✖ Risk of applying at too high a point in the wall and therefore proving ineffective

✖ Can cause extensive damage if used incorrectly (e.g. applied to a wall that doesn’t actually need any treatment)

Drainage Channel Cost

The idea of a drainage channel is to create a system that effectively lets water flow through and from a given area and thus removing any surface water that might accumulate at specific spots.

In turn, this can stop rising damp. It is one of the most common solutions to repeating rising damp problems. Often, a path (of gravel or concrete) or concrete paving stones will be laid too.

Pros:

✔ Great answer for many cases of rising damp

✔ Interior work is not required

Cons:

✖ The final look may not be your cup of tea

✖ Can be time-consuming

Painting

One option is to paint over plaster that has been discoloured by rising damp. This is a straightforward job and costs about £25 a tub. However, it isn’t a solution to the source of the problem.

It’s more of a quick fix and short-term aesthetic solution. If rising damp is a recurring issue, you should hire a rising damp specialist to fix the actual core issue.

Pros:

✔ Cheap and effective

✔ Quick treatment of rising damp

Cons:

✖ Won’t solve the rising damp problem itself

✖ Not a long-lasting rising damp in walls treatment

What Does Treating Rising Damp Involve?

1. Hiring a Specialist

Though you can undertake this work yourself (see the next section for more details), if you have any doubts of what the work entails or the issue is particularly extensive, you should hire a professional. You could do so by asking your friends and relatives for any recommendations they may have or/and by looking for contractors and companies in your area.

Preferably, you should find an experienced specialist with plenty of references or positive online reviews. You may want to consult with the specialist regarding what type of damp proofing should be used. Though, it may be easier for you to ask them to go out and take a look if they deem it necessary before choosing the right approach for your property.

2. Damp Proofing

We’ll now take a look at how different types of DPC are installed or applied.

Damp Proof Membrane

1. First, remove old plaster as well as any degenerating surfaces.
2. Cut the membrane to the right size.
3. Position the membrane on the wall.
4. Fold it neatly around the corners.
5. Drill the DPM to the walls to fix it in place. Make sure that it’s secured.
6. Add a suitable wall finish to the DPM.

1. Following the manufacturer’s guidelines, prepare the area (e.g. the surface must be made sound and any holes filled with mortar). The surface should also be clean.
2. Apply a primer if suggested by the manufacturer.
3. Install 1-2 coats of liquid DPM.

DPC Injection

1. With a drill, create 12mm diameter holes with 115mm of space between them in the mortar. This could alternatively be done through the brickwork by drilling at a down angle to meet the mortar. The drilling area should be a minimum of 150mm outside, above, or adjoining the level of the ground.
2. Ensure the extension nozzle is attached to the cartridge tube correctly. Load it into the skeleton gun.
3. Inject DPC cream from the bottom entrance to the hole and out, until the hole is filled.
4. Either add a plastic plug to the holes or close them off with mortar.

Drainage Channel

1. Dig a trench along a wall or around the entire house. This trench should be roughly four brick courses beneath the DPC and have a width of around six to eight inches.
2. Pebbles, at least the size of golf balls should be used to fill the trench.
3. Add the path or concrete paving stones, if applicable.

Painting

1. Ensure the surface is prepared.
2. Apply 1-2 coats, depending on the producer’s recommendations.
3. Let the surface dry.

3. Additional Costs

There are plenty of extra jobs you might want to get out of the way at the same time. To have one wooden roof joist repaired will cost you around £400 to £475. If a metallic joist needs to undergo repairs, expect a bill of about £550 to £650.

To replace an entire roof may cost somewhere in the range of £2700 to £3450.

If you’d like to freshen up the room with a regular paint job after the damp proof treatment is fully complete, it will cost around £16 an hour plus the cost of the paint.

To have new skirting boards and flooring joists fitted will likely set you back £200 to £600 for a regular task. However, say if you wanted to remove the whole flooring for a standard living room and have new joists and chipboard flooring fitted, you’d probably pay around £1000 to £1320.

If a planning permission application is necessary, it would probably cost £150 to £250 and should any building regulations fees apply, it may cost up to £200 to £250.

DIY Rising Damp Treatment

As alluded to in the previous section, undertaking this work DIY isn’t always suitable, and the work can be tricky and generally requires a particularly precise approach. That said, in some cases, you could consider performing some of the work yourself while having a professional deal with the more complex aspects of the job. If you were to fit a DPC and do so in the incorrect way, you risk causing damage to your property.

There are also always risks when dealing with chemicals or tools like drills and hammers. If you decide to do it DIY, just make sure you take all of the necessary safety precautions and follow any guidelines provided by the manufacturers of the different products used.

Any damp proofing will typically fall under permitted development unless it is expected to be part of a bigger project. You’re most likely to fall into planning permission territory with the exterior work involved in creating a drainage channel.

Planning Portal covers a range of building regulations for drains and sewers and the regulations that apply to damp proofing, in general, can be found in Approved Document C.

Among these regulations are that any DPC work performed on a wall should be a minimum of 15mm above ground level for an external wall and that it should be a minimum of 22.5mm over the bottom point of a cavity wall cavity with the exception of where a cavity tray has been fitted. Also, any DPC or DPM in the floor should be joined up with the new installation(s).

An appropriate professional should sign off on your work where approval/applications were necessary. Rising damp DIY treatment can save you a lot of money but should only be undertaken if you know what is required.

Potential Problems and Pitfalls

As mentioned, incorrectly performed damp proofing can cause serious damage to a home. The work is also fairly disruptive and may take several days, depending on the scale of the work.

If you fail to get approval for planning permission or building regulations, you’ll need to analyse the reasons for the rejection(s) and re-apply with the relevant changes to your plans. However, this is an unlikely scenario, if any such approvals are even necessary in the first place.