Extreme Climate Masonry Water Seal
Stops penetrating damp dead in its tracks
Extreme Climate exterior water seal was developed with the structural waterproofing professional in mind, to solve those intractable penetrating damp problems that standard masonry sealing products were failing to overcome. So, we ignored the existing wisdom on costs and simply used the best liquid waterproofing technology available, to make an exceptional damp wall sealer. Customer feedback is almost unanimous, that Extreme Climate has saved many times its price compared to wasted diagnosis efforts and repeat repairs with cheaper alternatives.
Extreme Climate performs time and again, where other masonry water repellents have failed, especially in coastal or upland locations.
• Stops lateral penetrating damp
• Brush or spray applied it is 100% breathable
• 10-year exterior sealant lifespan
• Invisible when cured
• Brick sealant, stone sealant and mortar joint sealant in one easy application
• Protects masonry from the effects of the freeze/thaw cycle
• Controls the emergence of white salt staining on masonry
• Improves energy efficiency by reducing evaporative heat loss
How does it work?
Extreme Climate is manufactured from an ultra-premium hydrophobic concentrate which lines the microscopic channels or pores of mineral based building materials, rather than blocking them. This breathable solution is delivered in a fine distillate dispersion (spirit based) which facilitates superior penetration into the brick, stone or mortar being sealed. It is also very easy to apply.
The practical applications are numerous and diverse:
• Sealant for stone walls, brick walls and even concrete
• Protects exposed gable elevations from driving rain
• Clear water-proofer for new lime mortar pointing
• Solves leaks in porous sandstone
• Stops ingress around stone lintels
• Leaks in window reveals
• Suppresses unsightly efflorescence on new builds
• Seals problem chimney structures
• Controls moss and mould growth on walls
• Seals limestone without the darkening associated with conventional treatments
• Succeeds where other brick and stone sealers have failed
• Outperforms damp wall paints, whilst also preserving the original texture
One of the most common calls to our technical help desk is from frustrated homeowners, who have commissioned lime mortar re-pointing work to solve a penetrating damp issue, which typically shows up as damp patches on the interior plaster. The theory goes that the wall has been repaired over the years with Portland cement pointing (in place of lime), or even a full cement render, which is surely trapping moisture and preventing the wall from breathing. Re-pointing with traditional lime mortar will restore the natural breathability of the stone or brick-work.
This may well be true but all too often the desired “breathability” is accompanied by leaks…..lots of leaks… and understandable frustration. It’s not usually that the masons have done a bad job, or that the mix was faulty, but lime mortar is curious stuff. It doesn’t actually cure, it carbonates… a process which takes decades. But you don’t have decades, you need dry walls today and Extreme Climate has a strong track record of sealing walls, without compromising the carbonation process, breathability or heritage appearance of lime mortar.
Chimneys are another common source of moisture ingress, with particular problems relating to thermal cracking, carbon contaminants and structural vulnerabilities. Dark coloured damp patches, salt damaged plaster and black mould growth are typical chimney related problems. Extreme Climate can assist with remediating many of these issues by expediting the drying out of saturated masonry.
Sealing a wall or chimney with Extreme Climate has further benefits by reducing the problem of condensation and black mould which develop on the indoor side of wet exterior walls. By halting rain saturation it fractionally raises the wall temperature which in turn greatly reduces the problem of condensation forming inside.
Extreme Climate also helps to keep buildings clean by forming an effective stain shield against airborne dirt and other contaminants, which would otherwise be dissolved by rainwater and leeched into the substrate where they leave unsightly marks.
How to use Extreme Climate
Wire brush and scrape out all loose moss, mould and surface debris. You can scrub heavily soiled areas with warm water and detergent or in the case of sound walls, it may be more efficient to pressure wash, especially if the mortar joints are to be repointed. Where the wall is contaminated with white efflorescence (salts), you should clean these with
Kingfisher Eco Brick Cleaner.
Having cleaned the wall, spray the entire surface with
Kingfisher Bio Wash. This effective fungicidal wall solution neutralises moss and mould root systems/ spores so that they do not re-grow.
Re-point mortar joints
Moisture ingress through defective pointing is one of the most common causes of penetrating dampness. Rake out all loose mortar so that you work back to a sound substrate bed and re-point using
Kingfisher Pointing Solution in your mortar mix.
Masking off and temporary precautions
Extreme Climate is a white spirit (flammable) dispersion. Take precautions to exclude fumes from entering the indoor space by closing trickle and brick vents etc. You must exclude all sources of ignition and mask off windows / doors to avoid contamination of glazed surfaces.
Extreme Climate is supplied ready to use and should be applied directly to the substrate by low pressure spray or brush. Only one coat is required unless the surface is exceptionally porous in which case allow at least 48 hours between coats. Start at the top of the wall and work methodically downwards. Apply to refusal.
The most popular method of application for smaller projects is to apply by brush and you can use most trade grade brushes for this purpose. Decant the Extreme Climate into a standard paint kettle and work to your left or right, never overhead. For larger areas use a
manual solvent resistant sprayer.
How much will I need?
The coverage rate is 4 to 6 sq m per litre, so a 40 square metre frontage might on average require 8 litres. When working out the size of area to be treated do not deduct for windows and doors, this over-complicates the calculation. In any case the window reveals & sills add up to more surface area than you might think.
a) Not suitable for flat surfaces or shallow gradients, Extreme Climate repels droplets not “mass” water (puddles)
b) Do not apply to damp surfaces or in wet weather
c) Not for use indoors unless well ventilated during application and curing
As always we recommend that you read the Technical Data Sheet & Safety Data Sheet thoroughly before commencing any work. If in doubt please call us for advice, we are here to help.
“Extreme Climate” ONE COAT water seal is a solvent-borne, masonry water repellent, which arrests penetrating
damp using the latest hydrophobic liquid technology. At a molecular level Extreme Climate line rather than blocks
the micro-fissures and capillaries of mineral based building materials like brick, stone, and mortars, creating a 100%
breathable surface treatment. Developed for the exacting requirements of the remedial damp proofing and
building restoration trades, Extreme Climate has a 10 year minimum life without surface darkening. The formula
effectively halts rainwater absorption offering truly exceptional hydrophobic or "bead up" water repellence.
Companion / Related Products:
• Kingfisher Bio-Wash
• Kingfisher Pointing Mortar (Heritage Lime / Dark Grey / Light Grey & Sandstone)
• Kingfisher Pointing Solution
• Kingfisher Solvent Resistant Sprayer
Refer to these individual product data sheets for detailed application guidance published on our website
Extreme Climate is suitable for application to most types of vertically built masonry, primarily external walls but
also including chimney supporting structures and buttresses. It is also a useful protection on steeply raked
stonework and for sealing radius topped or pitched profile coping stones. Extreme Climate is a premium grade
water seal and as such enjoys class leading versatility, in terms of the multitude of materials it can be applied to
including, but not limited to:
• Facing brick
• Common brick
• Lime mortar
• Portland cement
If in doubt, please call Kingfisher Building Products on Technical Dept. Tel: 01229 869 100.
1. Breathable Protection:-Extreme Climate repels mass water (e.g., rain drops) but does not “seal” the substrate
or “trap” moisture within it. Rather it works like modern, waterproof clothing, preventing water ingress whilst
allowing vapour to escape freely from the substrate. This is what is often referred to as “breathable” but in fact
means vapour permeable – allowing moisture to escape (evaporate) naturally from the structure.
2. Invisible Shield:-From a heritage or simple aesthetic perspective it is crucial that protective treatments should
not compromise the essential character or appearance of a building’s surface texture. Extreme Climate therefore
leaves no surface “finish” or “sheen”, doesn’t darken stone or brick and is completely invisible once cured. Extreme
Climate penetrates most masonry to a depth between 1.5mm to 5mm, depending on the density and porosity of
3. Protection from weather damage:-Most common building materials (brick/ stone/ mortar / block) are mineral
based and are therefore ultimately prone to moisture absorption, especially when exposed to the elements over
long periods of time. Water is a persistent invader and will exploit tiny fissures in masonry to work its way deeper
and deeper, into the fabric of a building by capillary absorption. This moisture ingress is exacerbated by the freeze
/ thaw cycle which spalls masonry and further expands the tiny cracks and fissures in a continuous cycle of decay.
Extreme Climate halts this destructive cycle by creating an invisible, hydrophobic barrier which repels rainwater
and prevents the moisture from absorbing in the first place.
4. Protection from organic growth:-As weathering increases the porosity of masonry, moss and green mould can
begin to take hold. Extreme Climate inhibits moss and other organic growth by robbing it of the water and nutrients
drawn from damp masonry. This is an important factor because moss in particular exacerbates water absorption
by retaining moisture and sending damaging roots into the substrate.
5. Protection from penetrating damp:-The factors described above can ultimately lead to penetrating dampness.
Penetrating dampness occurs when moisture migrates all the way through the wall to the interior of the building –
often during periods of prolonged heavy rain when the walls are continuously absorbing water. This “mass water”
absorption combined with capillary action shows up on internal decorative finishes as damp patches on plaster,
peeling wallpaper, salt damage, black mould etc. It is often accompanied by an unpleasant musty odour. Extreme
Climate stops penetrating damp by eliminating mass water penetration.
6. Reduces condensation:- Even if a wall is not actually leeching moisture all the way through to the internal plaster
(penetrating damp), partial saturation can still cause “cold bridging” whereby exterior cold is transmitted through
the wall to the interior causing a “cold spot”. Drying out with Extreme Climate reduces the problem of warm moist
indoor air condensing on the “cold spot” surface and breeding black mould growth.
7. Keeps buildings cleaner:-Damp porous surfaces tend to readily absorb airborne dirt, carbon and other pollutants which are then dissolved in rainwater and carried into the top 2 to 3 mm of the masonry. This dirt builds up over time and can lead to unattractive dark stains. Extreme Climate’s molecular structure prevents the moisture
absorption thus breaking the cycle and does not change the colour of the material to which it is applied.
8. Energy Efficiency (reduces evaporative heat loss):-Using Extreme Climate to dry out a damp wall can also reduce evaporative thermal loss because a wet wall is a cold wall and "bleeds" heat to atmosphere faster than a dry wall.
9. Efflorescence control (salt staining):-A common problem which blights the aesthetic appeal of many properties is “efflorescence" or "salting" which is the unsightly, white staining we see on so many “new build” walls. This occurs because walls are built of mineral based products including clay, sand, and cement, all of which come from the ground, which in turn is naturally full of chlorides (salts). These salts only come out of the masonry “in solution” i.e. when the surface gets wet from rainfall etc. As the wall dries out after rain, the water evaporates leaving the white salt crystals. Extreme Climate can help by limiting the moisture absorption / evaporation cycle which leaves mineral salts deposited on the surface. Please call us for detailed advice on treating efflorescence.
In general, it is very important that the surface to be treated is dry and masonry joints are sound, free from cracks
and that all organic growth and accumulated contaminants are removed before application. As with all surface
treatments you should apply to a small test area to check for compatibility before proceeding to full application. It
is the user’s responsibility to establish suitability for the task in hand. Note: Extreme Climate can also be used in
some instances to protect interior stone finishes but is best applied during construction/ re-fit phase when residual
odour is less of an issue than in occupied premises.
1. Cleaning:-Remove all loose moss, mould and dirt by wire brushing or otherwise gently abrading the affected
areas. Depending on the type of surface contaminant it may be appropriate to clean with a scrubbing brush in warm
detergent solution. In the case of reasonably sound walls and in the context of a full renovation where the building
interior is stripped out, it may be more efficient to pressure wash the surface, especially if the mortar joints are to
be repointed anyway. Where the wall is contaminated with white efflorescence (salts), you should clean these with
Kingfisher Eco Brick Cleaner.
2. Sanitise with Kingfisher Biocidal Wash:-Having cleaned the wall down and removed all visible traces of organic growth you should spray the entire surface with
Kingfisher Biocidal Wash. This effective fungicidal wall solution is designed specifically to neutralise moss and mould root systems/ spores so that they do not re-grow.
3. Re-Pointing:-Your cleaned and biocide treated wall is now ready for re-pointing and any other necessary repairs.
The re-pointing is extremely important as rainwater ingress through defective pointing is one of the most common
causes of penetrating dampness. Rake out all loose mortar so that you work back to a sound substrate bed and re-
Kingfisher Pointing Solution in your mortar mix to massively improve adhesion, strength, and water resistance. Where an entire wall needs to be re-pointed, we recommend using
Kingfisher Pointing Mortar to help achieve uniform colour continuity.
4. Masking off and temporary precautions:-Extreme Climate is a fluorocarbon dispersion in white spirit
(flammable) and has an odour similar to white spirit. You should therefore take sensible precautions prior to
application to exclude it form the indoor space including close all windows, shut trickle vents, check mastic joints
are in good condition and temporarily cover air brick vents and any other vents, cracks or apertures which might
permit the passage of Extreme Climate into the building. You must exclude all sources of ignition e.g. make sure
that all warm external flues (e.g. for central heating boiler) are cool during application. You should also mask off
windows / doors to avoid contamination of glazed surfaces.
Extreme Climate is supplied ready to use and should be applied directly to the substrate by low pressure spray or
brush. Only one coat is required unless the surface is exceptionally porous in which case allow at least 48 hours
between coats. Note: Extreme Climate does not stick to itself, so do not be tempted to apply a second coat unless
the primary coat is clearly not repelling moisture. The wall should be completely dry for at least 24 hours prior to
application and no rain should be expected for 24 hours post application. You should expect some residual odour
for 24 to 72 hours post application, but this is normally minimal if you follow the directions in section 4 above.
Extreme Climate is a mobile liquid with the consistency of white spirit, so it is preferable to start at the top of the
wall and work methodically downwards. In this way you will continually “catch” and spread any drips or runs,
minimising waste. Apply to refusal, this applies to both spray and brush application methods. In warm conditions
Extreme Climate dries quickly and the invisible finish means it can be challenging to remember which parts have
already been treated. Keep a piece of chalk handy to mark where you have finished if taking a break or stopping to
refill a sprayer. You should take sensible precautions to guard against overspray or drips onto glass or proximate
Brush Application:-The most popular method of application for smaller projects is to apply by brush and you can
use most trade grade brushes for this purpose. A masonry brush for larger areas is ideal and a two-inch gloss brush
for cutting into window reveals etc. Decant the Extreme Climate into a standard paint kettle and work to your left
or right, never overhead. Decant the Extreme Climate into a standard paint kettle and work to your left or right,
Manual Sprayer Application:-Extreme Climate can be easily applied with a manual pump sprayer and indeed this
is the most popular method for treating multiple elevations on a domestic property. You will need a
solvent resistant sprayer These are distinct from general purpose garden sprayers, in that they are equipped with solvent resilient (non-rubber) seals which won’t break down on contact with the product. Extreme Climate is supplied ready-to-use and you can add as much as the sprayer reservoir will hold or as much as you are comfortable to carry. Always work spraying to your left or right and never with the spray vapour “raining” down towards your face, even if wearing correct PPE.
DPC Pump Application:-Damp proofing professionals with an electric DPC injection pump can apply the product
with the standard brass spray lance attachment. This is the fastest method of application. Always work spraying to
your left or right and never with the spray vapour “raining” down towards your face, even if wearing correct PPE.
* See Kingfisher website for current
solvent resistant sprayer range.
Flush your solvent resistant sprayer with clean “white spirit” and clean any brushes used with same. If Extreme
Climate cures on glazed surfaces you will have to skim over the glass with a window scraper (from most DIY stores)
but the key is to spray the glass liberally with glass cleaner first to lubricate the blade. You then polish it up with a
soft cotton cloth. Note: this is standard technique as used by decorators to remove cured paint from windows.
Allow to dry for approximately 12 hours. In case of light precipitation, the surface should be covered until dry.
Dependent on the porosity of the surface 1 litre of product should cover approximately 4 to 6 m2.
Kingfisher Extreme Climate is supplied in 5 litre cans and 20 litre bundles. (25 Litre cans if collected)
SHELF LIFE & STORAGE
• Store indoors in a garage or outbuilding. Shelf life of Kingfisher Extreme Climate is approximately 24 months from
date of manufacture
• DO NOT store at temperatures above 40°C.
• KEEP AWAY from sparks, open flames, and other sources of ignition
• Keep container tightly closed when not in use
HEALTH & SAFETY
• If applying by spray wear a face mask and eye protection
• Wear disposable gloves and overalls during preparation and application
• Avoid contact with skin and eyes
• If contact occurs wash immediately with plenty of water
• Keep out of reach of children
• Ensure good ventilation during application and drying
• Always dispose of empty packaging responsibly
• The product is flammable so do not apply near sources of ignition. NO SMOKING
• Keep children and pets away from treated areas until fully cured
• Do not allow run off to contaminate drains, waterways or planted areas
Before using this product read the Material Safety Data Sheet which can be obtained at
by calling the Kingfisher Technical Dept. Tel: 01229 869 100.
The information given in this product data sheet is given in good faith, based on current knowledge and experience.
It relates only to the specific material designated and may not be valid for such material used in combination with
any other materials or in any process. Such information is to the best of the company’s knowledge and belief,
accurate as of the date indicated.
All recommendations are made without warranty or guarantee, as to accuracy, reliability, completeness since the
conditions of use are beyond our control. It is the user’s responsibility to satisfy themselves as to the suitability and
application of such information for their own use
Sealed porous lintels and sill
My house has mock stone lintels and sills that the rain would soak through like a sponge. This stuff did the trick for me. I applied it liberally with a brush. The lintels just sucked it up and it did the trick.
Reviewed by Ian
17th c stone building
Easy to use and looks to be working well with wet weather so far
Reviewed by Dan