RadonSeal Deep-Penetrating Concrete Sealers

Concrete waterproofing, radon mitigation and more!

RadonSeal™ Penetrating Concrete Sealer is a reactive internal sealer, which penetrates deep into cementitious materials (up to 4 inches), chemically reacts, bonds and strengthens the substrate, and seals it against liquids and gases. Seals new or old concrete, indoor and outdoor.

RadonSeal was specially developed to provide the tightest possible seal, in order to seal concrete not only against water seepage but also against vapor and even the minute atoms of radon gas.

Concrete, mortar, or stucco are very porous. When concrete cures, surplus water moves to its surface, leaving behind a network of interconnected capillaries. Concrete is more porous than Swiss cheese – typically 12% to 18% air. By deep-sealing the pores (capillaries) inside concrete, RadonSeal prevents or solves the multitude of problems caused by its porosity:

• Concrete waterproofing - stops or prevents water seepage through concrete in basements, foundation slabs, retaining walls, and roofs
• Efflorescence - stops or prevents the unsightly "white powder"
• Damp proofing – seals against water vapor transmission, reduces humidity
• Radon mitigation - seals concrete against the infiltration of radon gas
• Mold remediation – reduces humidity and prevents the growth of molds 
• Dusting - hardens the surface flint-hard, reduces dusting and wear
• Makes concrete denser and stronger (up to 40% in flexural strength)
• Reduces concrete cracking – bonds and strengthens concrete, protects rebar against corrosion
• Protects driveways against freeze-thaw damage and road salts
• Resists alkalis and acids - protects against deicers and other chemicals, used in kennels
• Paints or floor coverings - protects concrete paints, stains, adhesives, and floor coverings against “alkali attack” 
• Deep-cleans concrete – purges contaminants, oil spills, and minerals
• Preservation – extends the life of concrete, protects against deterioration, pitting, spalling, and crumbling.

What is RadonSeal?

RadonSeal is the heaviest available silicate-based sealer, which penetrates deeper, carries more active minerals, and seals tighter than any other concrete sealant. It does not depend on gravity – it is also used on concrete walls and ceilings. In case of basement walls, RadonSeal is usually applied on the interior to seal against water seepage as well as the seepage of water vapor and radon from the ground. If there is an opportunity to apply it on the outside, it has the added advantage of preserving the exterior of the concrete and extending the life of waterproofing coating.

When concrete cures, it produces "free lime." RadonSeal chemically reacts with the free lime and becomes a silicate mineral – the same mineral produced by the hydration of cement, which bonds, strengthens, and seals the concrete. The results are PERMANENT! No re-application is ever needed.

Sealing with RadonSeal is like injecting portland cement into the pores in concrete. Simply, it results in a higher grade of concrete that is denser, stronger and tighter.

RadonSeal is a user- and environment-friendly waterborne sealer formulated for an easy and safe application.

More information: For more info on how RadonSeal works, the “alkali attack” and efflorescence, how to protect concrete, paints, and flooring against deterioration, and MSDS, visit Sealing Concrete

Unsure about your selection? Visit How to select the best sealer for your project

Quick and easy spray-on application

To apply RadonSeal, the surface must be bare (unpainted) – any paint or sealer, adhesives, grime, efflorescence, etc. has to be removed first.

Spray on RadonSeal with the common hand-pump garden sprayer in 2 or 3 successive applications. It is non-toxic, nonflammable, and non-hazardous. There are no chemical solvents, VOCs, or noxious fumes.

Application: For detailed instructions and tips for sealing various cementitious materials, please read Application Instructions and Tips.

Paintable and non-slippery surface

RadonSeal leaves no film or color on the surface, unless over-applied.

The sealed surface does not become water-repellent or slippery when wet. It does not "bead." It will absorb water drops (it “wets”) but a large puddle will stay, because the concrete is waterproof.

The surface remains suitable for paints or adhesives, thinset, patching, resurfacing, levelers, etc.

Uses for RadonSeal around the Home

• waterproofing concrete basement floors and walls or foundation slabs
• waterproofing mortar in stone foundations, porous limestone
• garage floors
• concrete driveways, parking areas, parking garages
• walkways, stairs, patios
• pool decks (if not colored)
• concrete roofs, exterior concrete walls
• concrete homes
• unpainted stucco, shotcrete
• potable water cisterns, reservoirs, fish ponds
• kennels, stables.

Before finishing your basement, protect your investment and seal the concrete with RadonSeal! Covering the walls and floor traps water vapor seeping through the porous surface, which sooner or later will cause molds, mildew, and the typical musty odors.

Your First Step when Moving

RadonSeal spray-on application makes it a quick and easy do-it-yourself home repair or home improvement project.

Selling your house

Before putting the house on the market, seal all the concrete in your basement to avoid any last-minute glitches at closing! Buyers are wary of fresh paint. Stop moisture problems and musty odors. Play it safe and reduce radon to a minimum – radon levels fluctuate widely and a bad short-term radon test can scuttle the closing.

Buying a home

If there is a radon or moisture problem, negotiate a discount for conventional radon mitigation or waterproofing. Then, do it yourself with RadonSeal and save! Protect your family's health by reducing dampness and radon to a practical minimum.

Newly built homes

Now is the best time to preserve the concrete, in order to prevent future moisture or radon problems. Sealing the concrete foundations is particularly important in today's energy-efficient homes, which draw not-so-fresh air through the concrete. Ask your builder or do it yourself.

Builders and Contractors using RadonSeal

RadonSeal reduces costs and warranty callbacks, improves results, adds value, and increases customer satisfaction for a variety of contractors:

Building contractors	Concrete contractors
Basement remodeling contractors	Waterproofing contractors
Radon mitigation contractors	Mold remediation contractors
Flooring contractors	Painting contractors

Volume discounts are available. Info for builders and contractors

Large Buildings and Concrete Facilities

RadonSeal prevents or solves problems with moisture, molds, and radon in residential, institutional or commercial buildings like schools, apartments, hospitals, and hotels. It preserves commercial and industrial concrete assets indoors and outdoors – warehouses, factory floors and walls, cooling towers, water treatment plants, and bridges. It also protects parking areas, garages, and factory floors against oil spills and most chemicals. Info on RadonSeal commercial applications

RadonSeal can be shipped in 24- or 36-pail shipping pallets and 55-gallon drums. Application contractors are available in some areas. E-mail us at commercial inquiries

The Long History of Silicate Sealers

The history of penetrating silicate concrete sealers dates back to Germany in World War II, when they were used to strengthen quickly poured thin military runways. After the war, the Army Corps of Engineers started using the sealers for the preservation of concrete dams and bridges. As the technology evolved, the use of silicate concrete sealers expanded from preserving structural concrete to waterproofing outdoor and indoor concrete. Somewhat diluted, they area also used as "surface hardeners."

During the last couple of decades, penetrating silicate concrete sealers have become widely used in the US and abroad, be it the Disney World or Sydney Opera House. Many architects specify them for major buildings. The sealers have been successfully used on thousands of major concrete structures and buildings.

Money-Back Guarantee

RadonSeal is effective in stopping water seepage, water vapor, molds and radon gas - see Homeowners' Testimonials

The seal is permanent - backed up by a Limited Lifetime Guarantee !

How Much RadonSeal Do I Need?

RadonSeal is shipped in 5-gallon pails and a typical basement needs 2 (or 3) pails. Also available in 2.5 gal. size (1/2 pails) or 55-gal. drums. Typical coverage:

	Poured concrete	1,000 sq. ft. per 5-gal. pail (in 2 applications)
	Concrete blocks	500 sq. ft. per 5-gal. pail (in 3 applications)
	Cinder blocks	400 sq. ft. per 5-gal. pail (in 4 applications)

The shelf life of RadonSeal is one year. Unopened pails in salable condition are returnable. Check out Commercial Terms.

RadonSeal Selection and Prices

There are two different grades of RadonSeal to suit the size of the pores in concrete.

• RadonSeal Standard penetrates better into newer and tighter poured concrete.
• Use RadonSeal Plus on blocks (CMUs) or on poured concrete over 20 years old and outdoor concrete over 2 years old. 

	RadonSeal Standard	Normal strength for tight poured concrete in good condition. For basements or slabs, garages, and tightly troweled surfaces. Price $169 $149/5-gal. pail or $89/half-pail (2.5 gal.)
	RadonSeal Plus	High mineral content to fill larger pores. For concrete blocks or cinder blocks, and for older or already porous poured concrete. Price $189 $169/5-gal. pail or $99/half-pail (2.5 gal.)

Add shipping by courier to the lower 48 states at $24 per pail or $14 per half-pail.

Orders received by 2 PM EST are usually shipped the same day. The courier (UPS) delivers within 3 to 5 working days within the lower 48 states.

Shipping and Ordering

Orders received by 2 pm ET are normally shipped the same day and UPS Ground delivers within 3 to 5 working days in the lower 48 states. For shipping express and to other states or countries, and to Canada, inquire first by e-mail or telephone.

For the most secure and encrypted SSL online processing of credit card orders, just click ORDER ONLINE. Or you can make secure payments using PayPal. If you prefer mailing a money order or check, use the Order Form. Or simply phone your order in!