Frequently Asked Questions

Q. Re-line or replace?
More often than not, tanks are located in areas that have limited access and cannot be easily removed or replaced without major expenditure. Formatank will repair your in-situ tank with little or no disruption to existing plumbing.

The alternative to carrying out a repair in-situ inevitably involves grit blasting or mechanical scabbling, which is very noisy can only be done if the building is closed whilst the work is carried out.

Formatank liners are less sensitive to pits and other surface irregularities as they are thicker and, more importantly, will provide mechanical strength that will bridge small perforations that may result from corrosion. This simply cannot be achieved by painting alone.
Q. How much does it cost?
We understand that down time costs money, so we are always prepared to work with our customers to ensure that down time is kept to a minimum. Addressing these problems promptly by renewing tank and bund linings with GRP can save significant capital expenditure. We estimate that up to 80% of tank replacement and bund renewal costs can be saved by timely refurbishment with a GRP lining.
Q. What preparation work is required?
Because Formatank is a self-supporting lining it only needs the existing tank to act as a mould whilst the GRP is being laminated. Consequently, minimal surface preparation is required – simply dry the tank, remove loose scale and debris and apply a rust converting primer.
Q. What materials are used?
The materials that Formatank use are dependant on the use of the tank. All our materials are sourced from UK distributors with ISO QA systems for total traceability & excellent product knowledge. Water drinking tanks are relined using WRAS approved materials, whilst industrial tanks may require more careful material selection to offer the correct resistance to a wide range of fluids & gasses operating at ambient & higher temperatures.

With regards to water drinking tanks, all materials that we use are identified in section-2 of the WRAS (Water Regulations Advisory Scheme), based on BS6920 specifying the requirement for non-metallic materials that come into contact with drinking water in the UK.
Q. What about adhesion to difficult surfaces?
Shiny tank surfaces like glass-coated-steel tanks (vitreous enamel) are very difficult to laminate with GRP. In fact, we don’t know of any other company that can laminate directly onto glass-coated-steel without having to grit blast the surface beforehand, bringing with it serious health & safety issues and crippling costs. However, after researching worldwide for suitable adhesion products, we have developed our own primer that gives excellent adhesion to this particularly difficult substrate.
Q. What guarantee do you offer?
All our water tank linings come with a 10 years guarantee against poor workmanship & material failure. We can do this confidently since we have many GRP installations throughout the UK from the 1980’s that are still performing superbly.
Q. What do I need to do after lining my tank?
If your water system has been altered in any way i.e. after re-lining of water tanks, it is generally recommended that a sterilisation is carried out. Formatank can clean and disinfect your water system using a silver stabilised hydrogen peroxide biocide that is designed to be left in the system and allowed to degrade naturally overtime, thus allowing the use of the water during the disinfection process.

For an added piece of mind, Formatank can organise the risk assessments, regular inspection & testing of your water system to comply with the Health Safety Executive’s (HSE) Approved Code of Practice and Guidance L8 relating to legionnaires disease.

Legislative requirement for the control of legionellosis (legionnaires disease) put’s the responsibility for compliance clearly with the owner/operator of water systems. Under the Health and Safety at Work Act 1974 and COSHH regulations, all owner and operators of such water systems have a responsibility to ensure that the risk is controlled and kept to an acceptable level. The HSE Approved Code of Practice and Guidance L8 stresses that whilst the tasks required to be undertaken to control the risk may be contracted to an external specialist, the owner/operator must take all reasonable care to ensure the competence of the service provider to carry out the work on his behalf.
Q. What is GRP?
Glass-reinforced plastic (otherwise known as fiberglass or GRP) is a fibre reinforced polymer made of a plastic matrix reinforced by fine fibres of glass. It is an inexpensive, lightweight, extremely strong, robust material and can be easily formed using moulding processes.

An individual structural glass fibre is both stiff and strong in tension and compression—that is, along its axis. Although it might be assumed that the fibre is weak in compression, it is actually only the long aspect ratio of the fibre which makes it seem so; i.e., because a typical fibre is long and narrow, it buckles easily. On the other hand, the glass fibre is unstiff and unstrong in shear—that is, across its axis. Therefore if a collection of fibres can be arranged permanently in a preferred direction within a material, and if the fibres can be prevented from buckling in compression, then that material will become preferentially strong in that direction.

Furthermore, by laying multiple layers of fibre on top of one another, with each layer oriented in various preferred directions, the stiffness and strength properties of the overall material can be controlled in an efficient manner. In the case of GRP, it is the plastic matrix which permanently constrains the structural glass fibres to directions chosen by the designer. With chopped strand mat, this directionality is essentially an entire two dimensional plane; with woven fabrics or unidirectional layers, directionality of stiffness and strength can be more precisely controlled within the plane.

Contact Us


Formatank Ltd
Unit 5 Dunsdale Workshops
Dunsdale Road

For further information please email us here, or call us on 0800-085-4408.