Chimney Waterproofing Guide – Procedure & Best Products

Here, we’ll be discussing all chimney waterproofing and how to go about it.

The destructive action of moisture on chimneys has been a major worry for homeowners. Some of the most common moisture problems include spalling, rusting, and liner deterioration as well as damaged mortar.

Is chimney waterproofing necessary? Yes.

Chimney waterproofing is an effective way to deal with moisture problems.

It’s a solution to consider for persons having moisture-related issues too.  The tips provided here should be helpful enough to arrest any moisture penetration in your chimney.

How important Is Chimney Waterproofing?

Is chimney waterproofing important? Is it for everyone? These are only a few questions that may arise when chimney waterproofing is being discussed.

  • Should you waterproof your chimney?

First, it’s important to make it abundantly clear that chimney waterproofing is a very vital process.

In other words, the result of chimney waterproofing is to help extend its lifespan by improving a chimney’s general condition. When chimney bricks constantly get exposed to water, it soaks it up, thus creating a situation where water penetrates the flue and creates significant damage.

If you’ve noticed rapidly deteriorating mortar or empty spaces at mortar joints, chances are that such a problem is caused by moisture. The more moisture absorbed by mortar, the softer it gets and easily deteriorates when not attended to in a timely fashion.

Chimney waterproofing solves all of these issues, thus helping your chimney function normally. With basic maintenance actions, your chimney develops lesser problems.

What’s Involved?

For chimney waterproofing to be performed, several things must be considered. These include knowing how it’s done, selecting the best waterproofing products, and performing the waterproofing process.

Selecting The Best Waterproofing Products

Lots of chimney waterproofing products exist in the market.

These range from costly, to not too costly as well as those considered cheap. Experience has shown that the cheaper a chimney waterproofing product costs, the less effective it is.

Product constituents or ingredients are among the key factors to look out for. Chimney sealants or waterproofing materials having silanes or siloxanes should be preferred over those that don’t.

These constituents or ingredients are known to set up electrostatic charges on chimney surfaces.

Such charges will repel water from getting absorbed through chimney surfaces. This way, your chimney gets protected from the damaging effects of excess moisture.

  • Knowing How It’s Done

Whether you wish to perform chimney waterproofing yourself through DIY techniques or wish to call a pro, having some knowledge of the process will be in order. Basically, waterproofing is carried out using a sprayer.

The spray nozzle is aimed across every surface and the waterproofing contents are applied accordingly.

When doing this, it’s best to start from the bottom up. This technique ensures the contents don’t run down the chimney to be absorbed below the area being focused on.

So, the best strategy when performing chimney waterproofing is to start from the bottom up. Key areas to focus on during chimney waterproofing include mortar joints, chimney crown, and flashing area among others.

More will be discussed about this shortly.

  • Performing the Waterproofing Process

When carrying out chimney waterproofing, key areas are being considered for such application.

These include the brickwork or surface area of the chimney as well as the crown. The flashing area of a chimney also needs to be given extra care during the waterproofing process.

You don’t want to leave out mortar joints too. These should be sufficiently soaked to allow for proper waterproofing to occur. Let’s take a look at each of these points, shall we?

  • Chimney Brickwork or Surface Area

The chimney brickwork or surface is one area that should get a sufficient dose of waterproofing. These are mostly vertical surfaces that need to be systematically covered as explained earlier.

Starting from the bottom, steadily move to the top until all surfaces are sufficiently covered with the waterproofing material.

Consider using water-based waterproofing materials as they’re cheaper and less difficult in terms of shipping to your location.

  • Chimney Crown

The chimney crown is another component that shouldn’t be ignored. As the name implies, the crown is found at the top of lying horizontally. Waterproofing the chimney crown takes quite a different approach.

Because it’s a horizontal surface, a more thorough waterproofing job needs to be done.

Special coating materials are applied over the chimney crown. However, the crown needs to be prepared for proper application. Preparation will necessitate the use of wire brushes to get dirt and moss off the surface.

With most and dirt removal completed, the chimney crown is wetted before proper application of waterproofing material is performed.

When discussing moisture prevention, one of the primary parts designed to perform such is the chimney flashing.

This is mostly found at the joint between the roof and chimney. While it’s designed to limit or keep moisture out, chimney flashing won’t provide 100% satisfaction.

With chimney waterproofing, you stand to get enhanced moisture protection. Waterproofing materials with high-resin coatings are mostly used for such jobs.

Once applied, this chimney waterproofing material keeps out water and excess moisture by acting as a repellent and seal.

  • Mortar Joints

Mortar joints are among the most vulnerable when it comes to moisture and water penetration. These are points that require a significant level of dousing with waterproofing material.

With proper application comes a more water-resistant chimney that serves for a long time.

Chimney Waterproofing Lifespan

Waterproofing a chimney is expected to achieve an objective.

In other words, such protection is expected to last for a considerable period of time. In most situations, you should have at least 2 decades of protection from water exposure.

However, the lifespan is significantly lower in areas having significant weathering action. For such situations, the length or duration of time for waterproofing is significantly lower.

Chimney waterproofing is an important protective action performed to extend the condition of chimneys.

Excess moisture is known to cause all sorts of problems for chimneys. This doesn’t have to be so if you adopt maintenance procedures like waterproofing.

With the tips provided above, you should be able to have your chimney system adequately protected.

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