How Tank Insulation Is Priced
Commercial tank insulation is priced per project, based on the square metres of tank surface area, supplied and installed through the Duratite approved installer network. Prices vary widely between projects — a straightforward 5,000 litre GRP tank in a sheltered plant room sits at the lower end, while a rooftop tank requiring scaffolding, a thick specification and a silicone topcoat sits at the upper end. This article explains the variables so you can understand where your project is likely to fit before you ask for a quote.
We explain the drivers openly because facilities managers and estates surveyors are under constant pressure to benchmark capital spending, and opaque pricing helps nobody. The only reliable number for your specific tank is a fixed quotation following a free site survey — and that quotation itemises every cost line so it can go straight into a business case.
What the Price Actually Includes
The per-square-metre price includes:
• Supply of Nexseal LE closed-cell spray foam to the specified thickness.
• Supply of Gaco topcoat (U92, S42 or 127 as specified).
• Substrate preparation — degrease, abrasion or light cleaning as required on sound substrates.
• Installation labour by a Duratite approved installer.
• Masking and protection of surrounding surfaces.
• Curing time and Gaco topcoat application.
• Sign-off documentation — installation certificate and photographic record.
It does not automatically include: specialist access (scaffolding, cherry picker, abseil), substantial remedial work on failed existing insulation or corroded steel, DC315 intumescent coating (when required for fire separation), or project-specific RAMS documentation for unusual sites. These are quoted separately as a clearly itemised line on the written quotation.
Cost Factors Explained
Thickness of Nexseal LE
Thickness is the single biggest variable. 50mm (basic frost protection) is approximately 60% of the cost of 75mm (standard commercial spec), which is approximately 75% of the cost of 100mm (high-exposure spec). Thicker applications require more material and more passes of the spray rig, and on large tanks this adds up quickly.
Topcoat Selection
Gaco 127 acrylic is the most economic topcoat and is suitable for sheltered internal applications. Gaco U92 polyurethane is mid-priced and widely used for general external applications. Gaco S42 silicone is the highest-performing topcoat and carries a premium over U92, justified by its significantly longer UV life.
Tank Surface Area
Small tanks have a disproportionately high mobilisation cost. A 1,000 litre tank has roughly 6–8 m² of surface area, and the mobilisation cost (travel, equipment set-up, RAMS, first-fix) is spread over only that small area. A 50,000 litre tank has a much larger surface area, and the same mobilisation cost is spread much more favourably. For very large tanks or multi-tank sites, the effective rate per m² can drop by 20–30% compared to small isolated jobs.
Access
At-grade external tanks with free access are cheapest. Rooftop tanks with existing edge protection are next. Tanks requiring scaffold tower or cherry picker hire are more expensive. Tanks in confined spaces or requiring rope access are the most expensive. Duratite's survey will always specify the access method before the quotation is issued.
Geographic Location
Duratite's approved installer network covers Ireland and Northern Ireland, but mobilisation costs vary with distance and are confirmed at survey.
Get Free Advice or Book a Survey
Duratite's technical team provides free site assessments and fixed-price quotations across Ireland and Northern Ireland. No obligation.
Cost Drivers by Tank Type
The table below shows how typical commercial tank installations compare. Rather than indicative totals, it sets out the usual specification and the main factors that push the price up or down, so you can see what the survey will focus on.
| Tank | Surface Area | Spec | Main Cost Drivers |
|---|---|---|---|
| 1,500L sheltered plant room tank | ~9 m² | 50mm + Gaco 127 | Small area, so mobilisation is a larger share of cost |
| 5,000L standard commercial header tank | ~25 m² | 75mm + Gaco U92 | Standard spec; easy access keeps cost down |
| 5,000L rooftop tank, scaffold access | ~25 m² | 75mm + Gaco S42 | Scaffold access and silicone topcoat add cost |
| 10,000L external rainwater tank | ~40 m² | 75mm + Gaco S42 | Silicone topcoat for UV exposure |
| 25,000L hotel break tank | ~70 m² | 100mm + Gaco S42 | Thicker foam; larger area improves the rate per m² |
| 50,000L industrial process tank | ~105 m² | 100mm + Gaco S42 | Large area spreads mobilisation cost |
| 2,500L bunded fuel oil tank | ~12 m² | 75mm + Gaco U92 + DC315 | DC315 fire coating is a separate line item |
| AD slurry tank, 200m³ | ~180 m² | 120mm + Gaco U92 | Very large area; 120mm drives material volume |
Gaco Topcoat Selection and Cost
| Topcoat | Relative Cost | When to Choose It |
|---|---|---|
| Gaco 127 acrylic | Lowest of the three | Sheltered, internal plant rooms |
| Gaco U92 polyurethane | Mid-range | General external, abrasion |
| Gaco S42 silicone | Highest of the three | Exposed rooftop, 20+ year life |
| DC315 intumescent coating | Separate line item when specified | Fire separation requirements |
Access and Mobilisation Costs
Access costs are the biggest "hidden" variable in tank insulation pricing. As a working guide, from least to most expensive:
• At-grade, free access: usually no additional cost.
• Rooftop, existing edge protection: usually no additional cost.
• Scaffold tower hire: a modest additional cost, depending on hire duration.
• Cherry picker / powered access platform: charged per day of hire.
• Full independent scaffold: a significant cost line, depending on height and complexity.
• Rope access: specialist quotation required.
Payback Period vs Heat Loss
The financial case for tank insulation depends on what the insulation is protecting against. For frost protection, the payback is primarily avoidance of catastrophic burst tank events — a single incident can cost many times the price of the insulation in direct damage and business interruption, so the insulation pays for itself in risk reduction on the first winter it is needed. For legionella control, the payback is good water hygiene and the avoidance of remediation costs, enforcement action and reputational damage. For refrigerated tanks (bulk milk, cold store process tanks), the payback is direct electricity cost reduction, typically within two to four years.
A simple heat-loss calculation for a 5,000L uninsulated header tank in a 28°C summer plant room shows approximately 150–200 W of heat gain per square metre of tank wall. Across the full tank, that's 3.8–5.0 kW of continuous summer heat ingress — enough to push water temperature above 20°C within hours. Insulating with 75mm of Nexseal LE reduces this to approximately 0.5–0.7 kW, a reduction of over 85%.
How to Get a Fixed-Price Quote
Duratite issues fixed-price written quotations after a free site survey. The process typically takes one to two weeks from initial enquiry to quote in hand:
1. Email info@duratite.ie with basic tank details (type, size, location, any photos you have).
2. Duratite arranges a site survey at a convenient time.
3. Survey report and specification issued.
4. Fixed-price written quotation, valid for 30 days.
5. Installation scheduled with an approved installer.
Duratite — registered office Unit 3D North Point House, North Point Business Park, New Mallow Road, Cork, T23 AT2P. CRO 821494.