Sealants & Grouts

To permanently stop unwanted water flow

Simple and effective repair sealants

The polyurethane grouts within the SealGuard range – SealGuard II & Hyperflex - are unmatched for their efficiency, simplicity and cost effectiveness.

These products are professional grade, highly effective and field-tested products available for use in a multitude of applications.

Both products provide a permanent fix to unwanted water flow.  They are hydrophobic – using the moisture with which they come into contact as an element to their void-filling, high-ratio expansion.

SealGuard II & Hyperflex are both easy to apply, with simple instructions for use. 

Please note:Both products contain Diisocyanate in levels of 0.1% or above, as of 24th August 2023, adequate training is required before industrial or professional use of this product.

SealGuard II

SealGuard II is a dual component, highly reactive, early strength, hydrophobic polyurethane grout.

Used to control high flowing water leaks. SealGuard II can be used in very fast water flow rates - in flows of up to 3 litres per second (189 litres/42 gallons per minute), stopping leaks easily and permanently at a fraction of the cost of traditional methods.

With a reaction time of 1-3 seconds is so rapid that no washout is experienced, and a final result achieving a 900 psi (>60 bar) compressive strength when cured, this product can be used in manholes, culverts, bunds, or any brick or concrete structure which needs to be dry.

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Hyperflex produces a similar, though slower reaction; providing instant prevention of widespread, low flow rate infiltration and ground stabilisation.

Due to this slower reaction rate, it is used where the unwanted water is more widespread with a lower flow rate - its slower reaction rate allows the product to penetrate further before it reacts.

A pre-catalysed closed cell hydrophobic grout that does not shrink. The product has been successfully field tested on cracked and honeycombed concrete, voids between walls and the floor and ceiling, expansion joints, cold joints and pipe intrusions. This total effectiveness, and flexibility with such a range of materials, means Hyperflex is excellent for use in tunnels, manholes, car parks, bunds, ground stabilisation or anywhere else.

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What our customers say:

"Many thanks for recommending the Sealguard II system to us.  As you are aware we have had many problems at [the site we've been working on] in Bristol with water ingress and infiltration within both pipes and manholes.  Our client had used extensive labour and resources trying to plug with other products to no avail, however following the simple instructions we were able to seal up the remaining manholes in a fraction of the time and cost, and needless to say our client was delighted and impressed that we were able to find a solution."

Tom, Contractor, South West


"We had high volumes of water ingress into a brick manhole/chamber at a site in Gloucester and I contacted S1E to see if they had a solution.  Tony Hickman, Technical Sales Manager of S1E, explained how the SealGuard II product worked to permanently repair water ingress into any substrate. I subsequently ordered the SealGuard II Starter Pack, and a further 12 twin-tubes. The manhole/chamber was completely sealed within 2 working days.  Had it not been for SealGuard II the excavation would have cost between £8-£10K and taken a full working week to complete. The SealGuard II product worked at both a fraction of the cost and time. I am delighted with the SealGuard II results."

Warren, Groundworks & Construction company, Gloucester



S1E supply SealGuard II and Hyperflex repair sealants and grouts



Contact the S1E Sales Team for more information and orders by calling 01226 397 015, or emailing


Alternatively send your enquiry via the contact form below.




Our Sealants & Grouts range includes
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