Which Selleys sealant do you need, and how do you choose?

Sealants are not the first thing most people think of when it comes to protecting a house, but they do more work than their price suggests. A good seal keeps water and mould out, and can stop the spread of fire. Properly sealed doors and windows also reduce outside noise, help regulate room temperature, reduce energy bills, and keep insects and pollen out — and keeping moisture away from doors and windows prevents warping, which extends their life.

The Selleys range is large, but the choice is not as open as it looks. Almost every sealant purchase is decided by where the joint is — a wet area, a roof, a structural joint, a glazing bead, a fire-rated penetration — because Selleys formulates each sealant to do one specific job rather than to be adequate everywhere. Work out which of those you are dealing with and the range narrows to a handful.

What this category covers

The range runs from multipurpose sealants that give long-lasting protection around the home, through to silicones designed for specific materials. It is organised into seven sections:

• Wet area silicone — bathrooms, kitchens, laundries and showers.
• Roofing silicone — roof and gutter sealing and leak repair.
• Construction silicone — brick, concrete and structural joints.
• Glass — glazing and window frames.
• Fire rated sealants — perimeter and penetration seals in fire-rated construction.
• Multi-purpose — general sealing and adhesive-sealant hybrids.
• Other — sealant removal.

How to choose

Wet areas: bathrooms, kitchens and laundries

A wet area needs a mould-resistant sealant that can be applied precisely, dries quickly and gives a high-end finish. Selleys interior sealants are formulated to prevent mould and fungus growth, and the White for Life range is built around stopping yellowing and staining so a wet area keeps looking new.

The other practical variable in this section is the applicator. Selleys offers both caulking gun cartridges and ready-to-use tubes that need no preparation — which matters more than it sounds if the job is one short bead rather than a whole shower recess.

The range includes No Mould Silicone Sealant, White For Life Silicone Sealant, Wet Area Matt White Silicone, Pro Trade Wet Area Silicone and Fix & Go Bathroom & Kitchen.

Roof and gutter

Leaky gutters and roofs cause long-term damage to both the interior and exterior of a building, which is why this section is specified differently from the rest. Selleys Roof and Gutter sealants are 100% silicone, UV and weather resistant, and carry a 25-year guarantee against crumbling, cracking and peeling away.

Two things distinguish products within the section. Selleys says the range includes an option that leaves a roof rain ready in one hour and is applied without a caulking gun. And Storm Sealant gives an instant waterproof seal and can be applied in the rain — which is the property that matters when the leak is happening now rather than at the weekend. The range also comes in a selection of Colorbond colours so a repair is not conspicuous.

The full section is Roof & Gutter Silicone, Roof & Gutter Speed Seal, Roof & Gutter Spray Seal, Storm Sealant and Pro Trade Roof & Gutter Silicone.

Where UV and weather exposure is the problem

Australian homes take a lot of sun, driving rain and storm. Selleys frames this as a distinct selection criterion, offering products with superior protection against UV radiation at one end and, at the other, sealants that can be applied directly to wet surfaces — even in the rain — such as Storm Sealant.

The reason to treat UV as its own decision is that UV failure is slow and invisible until it is not. A sealant that is watertight on day one but not UV stable will chalk, harden and crack over a couple of summers, and the leak returns without warning.

Structural and construction joints

Construction silicone covers the heavier work: Brick & Concrete Silicone for high-movement masonry joints, Flexiseal Multipurpose Sealant for high-movement areas generally, and the two polyurethane Pro Trade Joint Sealant LM and Pro Trade Joint Sealant FC products for high movement capability and fast cure respectively.

Materials that need special attention

Some materials need more care to look after properly, which is why Selleys makes dedicated sealants for glass, fire-rated seals, and electrical insulating applications. Glass holds Glass Silicone and Pro Trade Glass Silicone. Silicone 401 RTV was developed for form-in-place gaskets and electrical insulating applications in manufacturing.

Trade and specification work

Selleys Pro-Series sealants meet most sealing requirements of plumbing, roofing and building tradespeople. They include an acrylic fire and acoustic rated sealant for perimeter and penetration seals in fire-rated construction, with a service temperature range from -40°C to +150°C and excellent joint movement capability.

The fire rated sealants section holds Fireblock AC, Fireblock PA and Fireblock XT. These are not general-purpose products and should be selected against the specification for the construction, not by preference.

General sealing and adhesive sealants

Multi-purpose is where the hybrid adhesive sealants sit, including the 600 series and All Clear for a crystal-clear finish on windows, showers and glass, Paint Over Sealant where the bead must be painted, and Pro Trade All Purpose Silicone, a 100% neutral cure silicone containing anti-fungicide for hot and humid conditions.

Removing the old sealant first

Selleys Sealant Remover is catalogued under other. It is worth knowing about before you start: new sealant does not bond reliably over old, so removal is usually the first step rather than an optional one.

The safety divide across the sealant range

The sections above are organised by where the joint is. Hazard does not follow that organisation at all: the widest gap in this category is inside a section, between products that sit on the same shelf and do nearly the same job. Three things are worth knowing before you buy.

Group	Products	Classification
Reproductive toxicity — Danger	FlameFlex	H360 may damage fertility or the unborn child (Category 1A), plus H319. The only H360 product in the range
Dangerous Goods — Danger	All Clear, Sealant Remover, Roof & Gutter Spray Seal	All Clear: H225, Class 3, UN 1133, PG II. Sealant Remover: H304 may be fatal if swallowed and enters airways, H226, H336, Poison Schedule S5, Class 3, UN 1133, PG II. Spray Seal: H223, H229, H336, Class 2.1, UN 1950
Eye damage — Danger	Silicone 401 RTV, Fix & Go Bathroom & Kitchen, White For Life Silicone Sealant	H318 causes serious eye damage (Category 1) with H315 — the category above irritation
Warning — the bulk of the range	The neutral-cure and acetoxy silicones: No Mould, Wet Area Matt White, Pro Trade Wet Area, Glass Silicone, Brick & Concrete, Pro Trade Roof & Gutter, Storm Sealant, Pro Trade All Purpose, Paint Over Sealant, the 650 and 655 FC and 670 adhesive sealants, Auto Fix Auto Sealant, Auto Fix Windscreen, Auto Fix Marine, Fireblock AC, Fireblock PA	H317 allergic skin reaction and/or H319 serious eye irritation; several add H227 combustible liquid
Isocyanate-containing	Flexiseal FC	Stated as classified hazardous and containing isocyanates; no GHS detail is published on the page
Not classified as hazardous	675 Crystal Fix, Flexiseal Multipurpose, Pro Trade Joint Sealant FC, Pro Trade Joint Sealant LM, Auto Fix Instant Gasket, Instant Gasket High Temperature	No signal word, no hazard statements

FlameFlex is the one that changes who should be holding the gun. H360, reproductive toxicity Category 1A, is the most serious health classification anywhere in the Selleys sealant range, and it appears on exactly one product. Its own composition table lists every named entity at under 1%, so the classification is driven by a trace catalyst rather than by the bulk of the sealant — which is precisely why Fireblock XT, also an SMP fire-rated sealant, does not carry it. If a fire-rated joint is the requirement and anyone on the job is pregnant, breastfeeding or trying to conceive, the Fireblock products do the same class of work without H360. Whichever you choose, FlameFlex's own data sheet insists you consult the project fire certifier first, because a rating belongs to a tested joint design, not to a tube.

Three products carry a UN number, and that is a storage and vehicle question, not a wearing-gloves question. All Clear is UN 1133 Packing Group II, the same Dangerous Goods entry as a solvent-borne contact adhesive — from a cartridge that looks identical to the sealants beside it, most of which are undeclared for transport. Sealant Remover is the same Class 3 entry plus Poison Schedule S5 and H304, the aspiration hazard that makes swallowing it a call to the Poisons Information Centre rather than a wait-and-see. Roof & Gutter Spray Seal is Class 2.1 as a flammable aerosol. If you keep sealants in a work vehicle or a hot garage, those are the three to separate from the rest.

If an unclassified product will do the job, six of them will. 675 Crystal Fix is the notable one: an adhesive sealant with no solvents and no isocyanates, and no GHS classification, where the obvious alternatives in the same multi-purpose section are a Class 3 flammable liquid (All Clear) or an isocyanate-containing polyurethane (Flexiseal FC).

Comparing the sealants on the numbers that decide the joint

Two figures decide whether a sealed joint survives: movement capability, which is how far the joint can open and close as a percentage of its width before the bead tears, and service temperature, which is what the cured sealant tolerates once it is in place. Skin time only decides how long you have to tool it. Several products publish no specification table — Auto Fix Marine, 655 FC, Paint Over Sealant, Storm Sealant, Roof & Gutter Speed Seal, Spray Seal and Fix & Go — and are left out rather than guessed at.

Product	Movement capability	Skin time	Service temperature
Brick & Concrete Silicone	±50% (ISO 9047 B)	70 minutes	Approx. −40 °C to 140 °C
Fireblock PA	±40%, joints to 40 mm	See product page	See product page
Pro Trade All Purpose Silicone	±25%	4 to 8 minutes	−60 °C to 170 °C
Pro Trade Wet Area Silicone	±25%	4 to 8 minutes	−60 °C to 170 °C
Pro Trade Roof & Gutter Silicone	±25%	5 to 10 minutes	−60 °C to 170 °C
Glass Silicone	±25%	5–10 minutes	−60 °C to 150 °C
Roof & Gutter Silicone	±25%	5 to 10 minutes	−60 °C to 150 °C
No Mould Silicone Sealant	±25% (ISO 9047)	20 minutes	See product page
Pro Trade Joint Sealant LM	±25% (EN 15651)	See product page	−40 °C to +90 °C
Pro Trade Joint Sealant FC	±25%	See product page	−40 °C to +70 °C
Instant Gasket High Temperature	25% (ASTM C719)	5 minutes	−40 °C to 260 °C; 343 °C intermittent
Silicone 401 RTV	See product page	5 minutes	−60 °C to +205 °C; 260 °C intermittent
670 Fast Grab	±20% (EN 15651/1)	Approx. 15 minutes	−40 °C to +100 °C
675 Crystal Fix	±20%	Approx. 15 minutes	−40 °C to +90 °C
FlameFlex	±20% (ISO 9047)	Approx. 50 minutes	−40 °C to 90 °C
Fireblock XT	±20%	See product page	See product page
Flexiseal Clear	±12.5% (ISO 9047 B)	40 minutes	−20 °C to 70 °C
White For Life Silicone Sealant	See product page	10 minutes	10 °C to 35 °C as published

Movement capability spans a factor of four, and the range standard is not the top of it. Most of the silicones sit at ±25%, which on a 10 mm joint is 2.5 mm of travel in each direction. Brick & Concrete Silicone doubles that to ±50%, and Fireblock PA reaches ±40% on joints up to 40 mm wide. At the other end, Flexiseal Clear is ±12.5% — half the range standard and a quarter of Brick & Concrete. A masonry expansion joint or a long external control joint is where the top of that spread earns its price; using a ±12.5% product there is the ordinary reason a bead splits along one edge after a season.

Speed costs nothing here, which is the opposite of the acrylic gap fillers. In an acrylic filler, the fast products are also the least flexible. In this range there is no such trade-off: the Pro Trade silicones skin in 4 to 8 minutes and still deliver ±25%, the same as No Mould at 20 minutes, while the two slowest-skinning products in the table — Brick & Concrete at 70 minutes and Flexiseal Clear at 40 — sit at the top and the bottom of the movement range respectively. Skin time here tells you how long you have to tool the bead and nothing about how the joint will perform. Choose on movement first, then pick a skin time that matches the length of run you can tool in one go.

Service temperature separates the automotive and industrial products from everything else. The domestic silicones top out between 140 °C and 170 °C. Silicone 401 RTV reaches 205 °C continuous and 260 °C intermittent, and Instant Gasket High Temperature reaches 260 °C continuous with 343 °C intermittent — roughly twice what a bathroom silicone will take. Nothing in the wet area, glass or roofing sections is a substitute for those on an exhaust manifold or a flue. In the other direction, the widest-tolerance products run from −60 °C, which is well beyond anything an Australian or New Zealand building will see; the figure that actually bites is the upper one, on a dark roof or a north-facing metal flashing in summer.

Common questions

Which sealant should I use in a shower?

One from the wet area silicone range. Selleys interior sealants for wet areas are formulated to prevent mould and fungus growth, and the White for Life products additionally resist yellowing and staining.

Can I apply a sealant while it is raining?

Storm Sealant gives an instant waterproof seal and can be applied in the rain. Selleys also describes sealants that can be applied directly to wet surfaces as part of its UV and weather range.

How long do roof and gutter sealants last?

Selleys states that its Roof and Gutter sealants are 100% silicone, UV and weather resistant, with a 25-year guarantee against crumbling, cracking and peeling away.

What is the difference between a wet area sealant and a roof sealant?

They are formulated for different environments. Wet area products target mould and fungus growth and finish quality indoors; roof and gutter products target UV, weather exposure and long-term water resistance outdoors. Selleys designs each sealant to do one specific job, so they are not interchangeable.

Do I need a caulking gun?

Not always. Selleys offers both caulking gun cartridges and ready-to-use tubes that take no preparation, and the roof and gutter range includes an option applied without a gun at all.

Can I match a sealant to my roof colour?

Selleys sealants come in a range of Colorbond colours so a roof repair is not obvious.

Which sealants can be painted?

Paint Over Sealant is the product described as paintable, and as not cracking or shrinking. Do not assume other sealants take paint — check the individual product page.

What do I use for a fire-rated penetration?

The fire rated sealants range, developed for perimeter and penetration seals in fire-rated construction. Select against the construction specification rather than by general preference.

How do I get the old sealant off?

Selleys Sealant Remover is made for removing unwanted sealant and leaving surfaces ready for a fresh start.

Has the range won any awards?

Selleys states that it was named Australia's Most Trusted Brand in the "Sealants & Fillers" category in the 2024 Reader's Digest Annual Trusted Brands Awards, and that this was the sixth consecutive year it received the title.