Water damage of any kind is never good news and it is important to check the causes of any water stains you find on walls and ceilings right away, as they could be signs of a leak which, if not repaired can lead to far worse.
Ceilings and walls can often have smaller, older stains, which leave nasty brown patches making the room look shabby and worn, but simply painting over these stains typically does stop them from returning, so how do you block water stains on walls and ceilings and prevent them from ruining your decorating?
Clean the stained, water-damaged patch with a light bleach solution, then apply a couple of coats of stain block or white oil-based paint, this will seal the surface and prevent the stain from returning. You can then cover the area with wallpaper or emulsion. If you do not create this protective layer, then no matter how many layers of emulsion you apply, the water stain will return as a brown patch and continue to show through.
In this article, we will look at step-by-step instructions on how to block water stains on walls and ceilings, as well as possible reasons for walls and ceiling water stains.
Possible Reasons For Wall And Ceiling Water Stains
If you find brown water stains forming, I highly recommend you investigate quickly and find the cause, as any water stains on walls and ceilings right away can be signs of something far bigger leading to serious damage.
Without properly treating the cause of the problem no how often you cover a water stain it will always return, leaving your rooms looking shabby and tired. So let’s take a look at the most common issues that cause water stains around the house and what you should do to sort out the problem
Here are a few typical reasons why water stains appear on walls and ceilings.
Water dripping from the roof
Roof leaks are a common cause of water stains. Water will always leak downwards and the roof can be subjected to a lot of wear and tear especially in the winter months, water can and will find its way in through flaws in the waterproofing layer, sarking felt, broken roof shingles or tiles
Any damage to flashing or lead work near chimneys or gables needs to be repaired as do gaps surrounding drains or guttering, take a look at our article for tips on checking your roof for signs of damage to help avoid leaks
For roofing that is in very poor condition, it may be worth replacing the roofing rather than trying to patch it up.
Leaks from the bathroom or toilet on the upper floors
Other sources of unwanted water which will cause stains to appear on the ceiling and walls below include poorly connected drains from showers or sinks, these can often be small leaks that take time to develop, a leaking tap can also provide the source for water to create damage and stains.
Overflows that do not flow properly will also leak and cause damage, this leaking water will eventually find a way through small spaces in floors or walls and create moist regions under the floor, other leaky patches can be caused by clogged toilets, stopped or blocked sink drains, and clogged shower drains.
Dripping pipes and radiators
Water is present all over your house it runs through pipes to connect bathroom taps, drains, and radiators for heating.
Pipe leaks are a major contributor to water stains as they are often right above or behind the water stain. Nevertheless, the leakage or origin of the water seepage need not be exactly next to or above the water stain; it can occur somewhere else further away from the spot where the stain appears.
Poorly insulated pipes in the attic or roof space are a common cause of water leaks. Condensation can drip from cold surfaces and in freezing temperatures burst pipes cause all sorts of damage.
If a radiator appears to be leaking, locate and repair the body of the radiator, valves, piping, or bleeding spot (the place where cold air gets out from the radiator).
Pipes are often hidden under floors or behind walls and leaks can be difficult to find and worse to repair, but the problem should be fixed in order to prevent water stains from forming on the walls and ceilings.
How to Prevent Water Stains on Walls and Ceilings, Step-by-Step Instructions
What are the brown stains on ceilings and walls?
When leaking water reaches the plaster surface of walls and ceilings inside your home, it can form dirty-looking brown patches, which are unsightly and look ugly.
These darker spots are created as the moisture dries out and the water evaporates and mineral deposits and residue are left behind creating the brown discoloring.
When you come to treat and repair and redecorate your ceiling or wall your first top goal must be identifying and eliminating the source of the water stain and related dampness. otherwise, the stains will return.
You can inspect the area and your property yourself which is the way I would recommend, however, if you do not feel confident in doing this, the best course of action is to get the wall/ ceiling inspected by an expert.
There are plenty of local services that carry out house inspections with cutting-edge equipment. You can make a reasonable decision about your future line of action with the aid of reports, this may include needing a plumber or roofer to help provide any repairs,
If you choose this option then always look for at least three quotes to compare, before selecting a tradesperson.
But if you’re more into DIY, you can even do it yourself! Follow the steps in this article to help identify and fix the source of the water stain, then wipe, prime, and repaint over the water damage to recover your wall or ceiling’s spotless surface.
Find the underlying issue and fix it
The first step when addressing a water stain is always to find the leak’s (or, in exceptional circumstances, the flood’s) origin. Ideal locations to start looking are the rooftop, any radiator in the attic or the upper floors, as well as the upper floor bathrooms.
If a leak is being caused by the roof, look for and fix any deteriorating shingles, damaged flashing (the weather-resistant substance laid on the rooftop), or poor sealing surrounding roof vents. The roofing needs to be replaced if the leakage cannot be fixed.
If the radiator appears to be leaking, locate and repair the body of the radiator, valves, piping, or bleeding spot (the place where cold air gets out from the radiator).
Leaking upstairs bathroom
Replace any outdated sealant that may be allowing water to seep in and cause leaks, especially if they are originating from the upstairs bathrooms. Fix leaky faucets, blocked shower drains, and overflowed toilets that might cause the flooring to flood.
After that, it should be easy to stop further leakage – and water stains on the walls and ceiling – by making the required repairs or by seeking the assistance of a qualified roofer, HVAC technician, or plumber if required.
Use bleach to clean and get rid of the stain
Once you have identified the cause of the leak and it has been repaired, you can address the stain directly, beginning with a deep cleaning. This helps to remove the stain and prevent mold from growing.
Wipe the discolored region of the affected area with a moderate DIY bleach solution (1/2 to 1 cup of bleach with 3 cups of warm water). Make sure you wear protective gloves and glasses when handling bleach or any other chemicals
As the stain starts to fade it leaves traces of mold, oil, grime, or debris, and this can prevent paint and primer from sticking to the wall or ceiling, washing the area down with bleach solution will kill off any live spores and germs and help to remove grime and oil.
To begin, protect the work area by placing an old blanket, sheet, or drop cloth over the floor below the patch you intend to work on.
Cover any clean walls and furniture with dust sheets
If required use a ladder or work platform to the access area of the water stain.
I recommend that when using a ladder you have someone hold the base for safety, then carefully climb up to reach the stained area
Whilst wearing safety goggles and gloves, wipe the water-stained patch spot with a clean sponge dipped in the recently prepared bleach solution, working the solution into the surface.
Spritz water over the spot to remove the cleaning solution, then use a clean towel to blot the moist area dry.
You can cover the ceiling or wall trims with masking tape to shield it from paint and primer after the region has fully dried.
Apply a foundation, using a stain-repelling primer
It would be enticing to repaint over the wet stain at this point and get done with it. However, since they are water-soluble, indoor latex and emulsion paints, that are frequently used on walls and ceilings, are a bad idea for an undercoat over a wet stain.
A wet stain that comes into contact with rubber-based paint gets dissolved within the layer of wet paint when the paint cools, allowing the stain’s discolored mineral constituents to once more seep through from behind the paint to the wall or ceiling.
A primer that is petroleum-based, mildew-resistant, stain-repelling, and closely matches the color of the existing wall or ceiling is your perfect idea for a foundation coat to hide water spots on the wall or ceiling. Water stains can’t penetrate petroleum-based stain-repelling primers because they are insoluble in water.
These stain-repelling primers, unlike rubber-based paint, also include a large number of adhesives (polymeric materials that link with paint particles), allowing the primer to stick to the area efficiently over time.
Some paint manufacturers also have specific stain-blocking paints, these use a shellac-based mixture which provides a barrier preventing the brown discoloration from reoccurring. I often use Zinsser BIN primer to cover water-stained paintwork.
I also use at least 2 coats of stain-blocking primer before I apply any other paint to the surface, this helps build up a good barrier to prevent the stain from returning.
Use paint to coat the primer
Once the stained area has been covered, it will be highlighted by the freshly primed section which is often a few colors brighter or darker compared to the rest of the wall or ceiling. Once the primer has fully dried out and for a professional-grade cover-up, I like to repaint the whole surface with a fresh coat of emulsion, this will make the surface clean and fresh and eliminate any patches caused by mismatched or faded paint.
Use a good quality brush to cut in the edges near walls or corners, I favor the Hamilton professional range of brushes they are great quality and provide a top-notch, professional finish, and then repaint the surface using a wide, 12″ Roller (either a 3/8-inch nap cover to get a clean surface or a 3/4-inch to 1-14-inch nap for a more textural wall or ceiling).
Add a second layer of paint for some more even distribution after allowing the initial coat to dry for approximately 4 hours or as directed by the manufacturer’s instructions.
Once you have put in the hard work and the second coat has dried, you will be rewarded with a wall or ceiling that looks as good as new and as if no water stains ever existed.
In this article, we looked at how to block water stains on walls and ceilings, as well as reasons for wall and ceiling stains.
Prior to addressing wall or ceiling stains, it is crucial to identify the water leak’s origin. If there are water stains in your house, they should be dealt with as quickly as possible to prevent further damage.
Covering and preventing water staining is a fairly easy job for anyone even DIY beginners, by thoroughly cleaning the water-stained area and using a good quality stain-blocking primer, you can clean up any damaged walls or ceilings so that they look as good as new
For more information on painting and decorating take a look at our articles and guides to painting and decorating
This article was written by: Richard Quinton – The DIY Help Desk Owner, Engineer & technical specialist.
Richard is one of the key partners in The DIY Help Desk team. He is a qualified Engineer, writer, and publisher, educated to Master’s level. He is a keen advocate of DIY and home improvements.
Richard enjoys helping others to learn new skills and reach their goals and believes that passing his knowledge and experience on through his writing is an effective way to positively impact the lifestyles and wellbeing of others on a larger scale.