ACTFLEX PU200 PU injection resin
One-component hydrophobic polyurethane injection resin
Hydrophobic PU resin that foams on contact with water to stop active leaks in concrete.
How ACTFLEX PU200 goes on
ACTFLEX PU200 sizes and key figures
One-component polyurethane resin for sealing active water leaks and cracks in concrete. It reacts with water into a closed-cell foam that fills the crack and blocks ingress, with no mixing.
- Foam expansion
- 8–20×typicaldepends on water contact; free foam above 13× · TDS p2
- Foaming time
- ≈ 180–360 stypicalfree foam at 25°C and 50% RH · TDS p2
- Viscosity
- 500–600 mPa·stypicalat 25°C · TDS p2
- Bond strength
- > 2.28 MPatypicalto concrete · TDS p2
- Elongation
- > 100%typicalthick sections; > 250% in thin sections · TDS p2
- Full reaction
- 24 hourstypicalstable seal · TDS p3
- Hole spacing
- ≤ 200 mm10 mm holes at 45°, 60–100 mm deep · TDS p3
- Apply at
- Above 10°Csubstrate and material · TDS p2
- Pack
- 20 kgpail · TDS p2
From the FORSPEC data sheet, TDS-PU200 · Revision 3 · 12 November 2026. Times are at 25°C and 50% relative humidity unless the data sheet says otherwise. Typical = FORSPEC’s own typical value, not a laboratory-certified one.
Where ACTFLEX PU200 is used
Use it for
- Concrete crack injection: sealing active leaks in slabs and walls
- Basements and underground structures, foundations and retaining walls
- Tunnels, subways and below-grade infrastructure
- Dams, reservoirs, and wastewater tanks and channels
- Bridges and parking decks: cracks and joints exposed to moisture
- Manholes, pits and utility vaults
Know before you start
- Not a structural repair: use PROBOND 1100, CRACK PRO 1200PS or CRACKLOCK E400L
- Not below 10°C, not UV stable, and not for live movement joints
- Needs water to react: pre-wet dry cracks through the packers
- Not for potable water: do not use in drinking-water tanks or potable water structures
Its FORSPEC systems
How to apply ACTFLEX PU200
- 01
Drill
Drill 10 mm holes at maximum 200 mm intervals, offset from the crack and angled at 45° to meet it at 60 to 100 mm deep. Alternate sides of the crack where access allows.
- 02
Packers
Blow or vacuum out the dust. Insert 10 mm non-return packers leaving about 20 mm showing, and tighten each firmly with a T-handle wrench.
- 03
Pre-wet
If the crack is dry or low in water, inject clean water through the packers first to start the reaction. Keep pump and lines free of water.
- 04
Inject
Fill the pump about two-thirds, start at low pressure and build up. Vertical cracks: bottom packer upward. Horizontal: ends toward the centre. Move on when resin shows about 100 mm either side.
- 05
Finish
After full reaction, remove the packers and patch the holes flush with FORBUILD 100 or FORCRETE 100.
- 06
Clean
Flush the pump and lines with urethane thinner straight after use, then use pump cleaning oil for storage.
A short guide from the data sheet. Read the full ACTFLEX PU200 TDS before you start.
How much ACTFLEX PU200 do I need?
Polyurethane injection resin for leaking cracks
Crack volume = length × width × depth. The PU data sheets give no fixed rate per metre: estimate from the crack volume plus an allowance for porous zones, then check it on the first section. Packers every 200 mm, the most the TDS allows. Your pump also needs its own charge of resin to prime.
You need
0 packs
Where the figures come from
Crack volume = length × width × depth. The PU data sheets give no fixed rate per metre: estimate from the crack volume plus an allowance for porous zones, then check it on the first section. Packers every 200 mm, the most the TDS allows. Your pump also needs its own charge of resin to prime.
- Consumption: no fixed rate per metre: crack volume plus an allowance, confirmed by trial injection. TDS-PU200, R3, 12 Nov 2026, page 3
- Density at 25°C: 1.12 to 1.20 g/cm³. TDS-PU200, R3, 12 Nov 2026, page 2
- Packer spacing: 10 mm holes at maximum 200 mm intervals. TDS-PU200, R3, 12 Nov 2026, page 3
- Packs: 20 kg counted for all three resins. FORSPEC system figure
More: ACTFLEX PU200 product page · Negative side system · Concrete repair system
Drawings for the systems it goes in
FORSPEC standard details as PDF and DXF. Each sheet is a generic detail: the specification names the products.
ACTFLEX PU200 questions
Does ACTFLEX PU200 need water to work?
Yes. The resin reacts with water to foam. In a dry crack, inject clean water through the packers before the resin.
How much will it expand?
8 to 20 times, depending on water contact. At 10:1 water to resin it foams 16 to 20 times. At 5:1 it foams 8 to 11 times. Foaming takes about 180 to 360 seconds at every ratio (typical, 25°C).
How much resin do I need?
There is no fixed rate per metre. Estimate crack volume plus an allowance for porous zones and expansion, confirm by trial injection on the first section, and record use per packer.
What does hydrophobic mean?
The cured foam repels water, so the seal does not depend on permanent water contact to stay stable.
Can I use it for structural repair?
No. It is a water-stopping resin. For load-transferring repair use PROBOND 1100, CRACK PRO 1200PS or CRACKLOCK E400L.
Can it go across a moving joint?
Not on its own. Live movement joints need a purpose-designed movement joint system. Injected foam alone must not be relied on across them.
Used with ACTFLEX PU200
ACTFLEX PU200 TDS and SDS
Always work from the current data sheet. Every FORSPEC TDS and SDS →
Specify it. Or buy it.
Send the drawings or photos and FORSPEC comes back with the system, the details and the quantities. Or find a FORSPEC stockist for ACTFLEX PU200.