Johnstone’s Damp Proof Paint Review

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johnstones damp proof paintDamp proof paint is one of the most popular ways of dealing with damp problems in the home. On the face of it, that’s not surprising. After all, it’s one of the cheapest options around if you need to address damp issues. Not only that, painting just seems a lot less confusing than all those technical terms you hear about with damp: injectable damp proof courses, tanking, membranes and so on. What can be confusing, however, is which damp proof paint to buy. So, let’s look at one of the most popular brands on the market – Johnstones Damp Proof Paint, and see whether (borrowing a slogan from another well-known brand) it really ‘does what it says on the tin.’

As well as that, we’ll throw in a few general tips about damp proof painting for good measure too.

Damp Proof Paint – The Basics

Before we start to look at Johnstones Damp Proof Paint itself, let’s first think about when you should consider using damp proof paint as a solution to damp.

Damp proof paint can be used to treat a variety of damp issues but the key thing to remember is that it should only be used once the actual cause of the damp – the root of the problem – has been identified, treated and rectified. You can’t just apply a couple of coats of damp proof paint on a damp affected area to cover up the problem and hope it will go away. If the problem hasn’t been treated, it will come back. A lick of damp proof paint might mask it for a little while, but it won’t be for long!

That said, damp proof paint can be very useful. It can be applied to brick, cement, plaster and concrete and is effective when used as a waterproof layer under a render or to cover up damp stains on painted areas. It is particularly good for treating rooms which are naturally moist, such as kitchens and bathrooms.

Johnstones Specialty Damp Proof Paint

Johnstones Damp Proof Paint, like most others, can be used on plaster, stone, brickwork or cement. It can be used as a finished coat, if you wish – or you can apply a decorative emulsion overcoat if you prefer. If you take the second option, the damp proof paint essentially works as damp-proofing primer sealer.

It’s a little bit pricier than many of the other damp proof paints on the market, but don’t let that put you off – this is a quality product. Just as long as you are using it on a damp affected area that it is appropriate to use damp proof paint on, and you apply it correctly; you should get good results with Johnstones Damp Proof Paint.

The positives

If you look at review websites long enough, you are bound to stumble across a negative review of any product or service at some point – it’s just a sign of the digital age. But when you notice that the reviews of a particular product are overwhelmingly positive, it really tells its own story.

And that’s what you see with reviews of Johnstones Damp Proof Paint. Amazon as I write this gives it a score of 4.6 out of 5, based on 38 reviews – 28 of which were ‘5 star’. You can read more on their site here: Johnstone’s 307956 Damp Proof Paint – White,2.5

The flavor of the reviews are that the product is fairly easy to apply, delivers results and is useful to deal with various damp issues around the home: damp stains on ceilings following a leak ,condensation problems in bathrooms and painting after re-plastering, for example. Reviewers talk about it producing a thick coat and months after there being no sign of the damp issues returning.

The negatives

Although most users find it easy to apply Johnstone’s Damp Proof Paint, you should bear in mind that it is not like your typical matt or emulsion, it is much thicker and can take a bit of getting used to. It tends to work best when applying to smaller areas rather than entire walls. You can do this, of course, but you will need a bit of patience to get the consistency of the coat right.

You might find that the coverage – supposedly a rate of four square meters a litre – is a bit optimistic. Unless you are an expert with a paintbrush, you’ll probably find the coverage to be more like three square meters a litre, if you’re lucky.

You are likely to find that 2 coats are necessary. To be fair, that’s what the product says is ‘recommended’. It’s probably fair to say that two coats are a necessity, and three a possibility. You’ll need this to acquire the total film coverage.

The smell! This is often mentioned in reviews. To say it’s pungent is a massive understatement. You should always wear a protective mask and ensure that areas are very well ventilated. It’s completely safe, but highly unpleasant!

The verdict

Preparation and patience are the watchwords.

It is vital that you follow the preparation guidance to the letter. Applying damp proof paint is not something you can cut corners with. Prepare and treat surfaces carefully before painting, as instructed. You need to leave 16-24 hours between coats, and you must do this. Overall, however, Johnstones Damp Proof Paint is an excellent product and one that can be highly recommended.