How to make old walls waterproof?

Author: Mavis Watsica PhD  |  Last update: Friday, January 9, 2026

The Right Waterproofing Solution for Old Buildings
  1. Base coat: the Rinzaffo MGN Roman waterproofing salt-resistant lime base coat.
  2. Main coat: a main lime plaster coat, which can be a regular or thermal lime coat.
  3. Finishing coat (optional): a good quality lime finish.

How do you waterproof an existing wall?

6 Simple Steps to Waterproofing Exterior Walls
  1. 1) Inspect your walls. Before you begin waterproofing, it's important to inspect your walls for any cracks, gaps, or other signs of damage. ...
  2. 2) Clean the walls. ...
  3. 3) Apply a waterproofing sealant. ...
  4. 4) Install a drainage system. ...
  5. 5) Install a vapour barrier. ...
  6. 6) Regular maintenance.

What is the cheapest way to waterproof walls?

Waterproofing Paint: Applying a waterproofing paint or sealant is one of the most affordable solutions. These products are designed to prevent minor seepage and are readily available at hardware stores. Ensure the wall is clean and dry before application.

How do you waterproof already painted walls?

Any paint film will simply prevent the treatment from working. The only way to waterproof a painted surface is to remove the paint or apply a waterproofing masonry paint on top.

How to make an interior wall waterproof?

Mentioned below are the major interior wall waterproofing methods:
  1. Paint and Sealants. One of the most affordable and easy methods to interior walls is to use paint and sealants. ...
  2. Waterproof Membranes. ...
  3. Drainage Boards. ...
  4. Cementitious Coating.

Stop Damp Coming Through Your Walls With Dampseal

What is the best waterproof paint for interior walls?

Epoxy paint is suitable for waterproofing basements and concrete surfaces. Latex paint is easy to apply, quick to dry and offers effective protection against water and moisture. Latex-based waterproof paint is preferred for interior use on the walls and ceilings.

Can a wall be made waterproof?

While there are many methods that can be used, one popular method is to apply a waterproof coating to the walls, which will create a barrier that prevents water from seeping in.

What happens if you put DRYLOK over paint?

However, DRYLOK® cannot be used over an oil or latex-based paint on the inside of a building. DRYLOK® will adhere to these paints, but if it cannot penetrate into the pores of the masonry itself, it will not waterproof the surface.

What can I put over paint to make it waterproof?

You can waterproof most types of paint by coating them with clear polyurethane or acrylic. This method can be as effective as spraying a sealant, but may change the paint's appearance by adding a glossy or shiny finish.

Can you waterproof over existing paint?

The key to waterproofing over paint is using the same brand and paint type. If you don't, you'll likely have a lot of problems trying to create an even surface—there will probably be spots that are still unprotected by the water-based sealant.

What is the easiest waterproofing method?

Cementitious Waterproofing – Cementitious waterproofing products are considered as the easiest waterproofing materials to use. These are readily available from suppliers of masonry products like MCT UAE, and they're easy to mix and apply.

What can you put over drywall to make it waterproof?

The most popular way to waterproof your drywall is to use oil- or latex-based waterproofing primer. These primers are made by most paint manufacturers and are designed to prevent mold and mildew from growing on the surface of your drywall.

Can you waterproof internal walls?

Damp Proof Membranes can be applied internally with little or no surface preparation. However, it is very important to install the membrane correctly to prevent expensive water ingress in the future. They should be used in conjunction with a Damp Proof Course in outer walls to create a continuous barrier to water.

How to make paint waterproof for walls?

One way to make a water-based emulsion paint waterproof is to add a water-resistant agent, such as a silicone-based additive, to the paint before application. Another method is to apply a clear waterproof sealant over the painted surface once it is dry.

What is acrylic waterproofing?

Acrylic waterproofing is applied to concrete structures, such as foundations, retaining walls, and parking decks, to enhance their resistance to water penetration. These coatings provide a seamless and flexible membrane that guards against water infiltration, cracks, and spalling.

What does tanking a wall mean?

Wall tanking or “tanking” is a method of preventing water ingress by creating a completely impermeable waterproof barrier on an internal wall. When we refer to tanking walls, it's usually in reference to below ground structures like basements or as a precautionary measure on damp walls above ground.

Does waterproof paint really work?

Waterproof paint is a valuable tool for protecting surfaces against water damage and moisture-related issues. Its unique properties allow it to create a protective barrier to prevent water penetration while maintaining an appealing visual appearance.

Can I put sealer over paint?

Water-based sealers or top coats are a great option for most painted furniture projects. When applied they will add a layer of protection without altering the color of the paint. They are also less toxic and have easier cleanup when compared to their oil-based counterparts.

Does clear coat make paint waterproof?

Short answer is no. It's a water base sealer/coat, that can be light damp cloth cleaned, but it doesn't make it waterproof. So it wouldn't be able to go outside, be washed in sink or dishwasher etc. For those, you'd want to get something specifically for outdoors/waterproof/etc.

What is the problem with Drylok?

As Drylok is an indoor waterproofing sealant, it does not last forever. Drylok comes with a 7-15-year warranty, and while this is a very long time, it does mean that you may have to renew this sealant again in the future. Give AK Water Works a call to discuss a more permanent option.

What's better than Drylok?

Superior Waterproofing Performance: Crystalline Waterproofing offers a higher level of waterproofing performance compared to Drylok Extreme. Its crystalline technology penetrates into the concrete, forming insoluble crystals that block capillary pores and microcracks, effectively preventing water penetration.

Why is my Drylok peeling?

The damp is the problem that is causing the flaking, and therefore the sealant will simply get wet again and start to come off. The real issue is that your home is not properly waterproofed. If it was, moisture would not get trapped in your interior foundation walls at all, and could not cause the flaking.

How to make a wall waterproof?

The best way to waterproof exterior wall panels is by plastering them. Plastering not only enhances the cosmetic appearance of the walls, but also makes them solid, and protects them against water seepage.

How do you weatherproof a wall?

Once the structural integrity of your walls is up to scratch, you can use a waterproof façade cream to create an invisible barrier between the elements and the exterior of your home. This protects your home against driving rain, potential frost damage, and pollutants.

What is the best waterproofing method for exterior walls?

Choosing the Right Waterproof Method
  • Silicate Based Sealer. This reacts in concrete and masonry to build a waterproofing coating. ...
  • Waterproof Paint. This is like acrylic paints, with a significant difference in giving better performance. ...
  • Use Plaster Additives.

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