Industrial painting specification: what it must contain

A complete industrial painting specification states the exact scope of surfaces, the preparation grade and profile, the coating system with dry film thickness per coat, the accepted ambient conditions, the inspection hold points, the records to hand over, the repair method, containment and waste handling, and the warranties. Without these sections, quotes cannot be compared.

The specification is the document that says what will be done, how and to which standards. The quote says at what price. When the specification lacks detail, each bidder fills the gaps their own way, and the difference is settled on site through change orders or disputes. This guide is for maintenance managers and project managers who write or review a painting specification in Quebec or Ontario. It complements our industrial painting page.

Why does a precise specification change the result?

A precise specification changes the result because it sets the same rules for every bidder and gives inspection a verifiable reference. Coating quality is decided during preparation and application; if the specification does not describe them, nothing allows you to require them.

ISO 12944-8 deals specifically with developing specifications for new work and maintenance, and ISO 12944-7 with execution and supervision. SSPC-PA 1 is the North American reference for shop, field and maintenance painting. A specification can rely on these rather than rewriting everything, as long as it states which clauses apply.

What should the scope of work state?

The scope must say which surfaces are treated, which are excluded and in what condition they are handed over. It is the most often neglected section, and the first source of gaps between quotes.

• Items and surfaces. List of items, approximate dimensions or areas, reference drawings or photos.
• Exclusions. Equipment to protect, galvanized or stainless surfaces not to be blasted, nameplates, gaskets, instruments.
• Existing condition. Type of coating in place, possible presence of lead or other heavy metals, thickness, adhesion. A survey before tendering avoids surprises.
• Access and constraints. Height, scaffolding, confined space, work in an operating plant, hours, shutdown window.
• Owner-supplied items. Power, compressed air, water, laydown area, waste handling.

When the old coating may contain lead, the specification points to lead paint removal requirements rather than plain blasting.

How should surface preparation be described?

Preparation is described by a standardized cleanliness grade, a measurable surface profile and contamination limits. A phrase like "clean thoroughly" cannot be verified.

• Cleanliness grade. SSPC-SP or ISO 8501-1 designation (for example SSPC-SP 10 / NACE 2 or Sa 2½), chosen for the system and the service. Our NACE 2 / SSPC-SP 10 surface preparation guide explains the grades.
• Profile. Profile range required by the primer data sheet, measured per ASTM D4417 or ISO 8503.
• Dust and salts. Dust level per ISO 8502-3 and, in marine or chemical service, soluble salt testing per ISO 8502-6 and ISO 8502-9, with the limit set in the specification.
• Compressed air and abrasive. Air cleanliness per ASTM D4285 and abrasive requirements.
• Edges and welds. Preparation grade per ISO 8501-3 where it applies.

Abrasive blasting is often the heaviest item on the job: the specification should say whether it is done dry, wet or by another method.

How should the system and thicknesses be specified?

The system is specified coat by coat: generic product type, minimum and maximum dry film thickness, recoat windows and topcoat colour. The table below summarizes what a complete specification states.

Thicknesses are recorded in a dry film thickness log. The specification should also say what happens outside the range: touch-up, extra coat or removal.

Which ambient conditions should the specification set?

The specification should set minimum and maximum air and surface temperature, maximum relative humidity and the minimum margin between surface temperature and dew point. These values come from the product data sheets; the specification refers to them and requires that they be measured.

Dew point measurement follows ISO 8502-4 or ASTM E337, at a defined frequency and before each coat. In cold weather, the specification states heating, dehumidification and enclosure requirements, as explained in our article on cold-weather epoxy application.

Which inspection hold points and records are needed?

Plan hold points where work does not proceed without acceptance: surface handover, end of preparation, each coat and final inspection. Each hold point produces a signed record.

• Before preparation. Surface handover, removal of oil and grease per SSPC-SP 1.
• After preparation. Cleanliness, profile, dust, salts, ambient conditions.
• After each coat. Thickness, appearance, recoat window respected.
• Final. Total thickness, adhesion per ASTM D4541 or ASTM D3359 depending on the system, holiday test per NACE SP0188 for immersion surfaces.

Records include product batches, ambient conditions, readings, nonconformances and their corrections. Our coating inspection service can fill this role independently.

How should repairs, containment and warranties be handled?

The specification should describe the defect repair method, debris containment and warranties, otherwise these three sections turn into negotiations at the end of the job.

• Repairs. Area preparation, overlap onto sound coating, repair system, checks.
• Containment and waste. Containment level per SSPC-Guide 6, waste handling per SSPC-Guide 7 and provincial regulations. In an operating plant, see our article on blasting in operating plants and dust control.
• Warranties. Scope (labour, product or both), exclusions, warranty inspection. Duration is negotiated in the contract; it does not replace inspection during the work.

How to compare the quotes received?

Compare quotes by checking that they all answer the same sections, then by reviewing the declared deviations. A markedly lower quote often leaves out a step: preparation, containment, stripe coats or inspection.

A few questions help bring those gaps to light:

• Is the preparation grade the one in the specification, on every surface, including edges and hard-to-reach areas?
• Is the proposed system the specified one or an equivalent, and is the data sheet attached?
• Are containment and waste disposal included, with the planned method?
• Are the hold points and records allowed for in the schedule and in the price?
• Are the exclusions written down, rather than left implicit?

Our article on industrial painting cost details the factors that move the price. The chosen system should stay consistent with our protective coatings approach. Our crews and qualified subcontractors work from LaSalle, including the Quebec region and Ontario. Send your specification or photos through the request a quote form: pricing on consultation, reply within 24 business hours.

Frequently asked questions

What is the difference between a specification and a quote?

The specification describes the work and the standards to meet; the quote is a contractor's price offer in response to that specification.

Can a specification be written without a prior survey?

It can, but it is risky. Without a survey, the condition of the existing coating, the presence of lead and access remain assumptions, and the gaps are paid for in change orders.

Should the specification name a specific product?

It can name a generic type with performance requirements, or a product with an equivalence clause. Either way, it sets the acceptance criteria for a substitution.

Who carries out the inspection in the specification?

The specification says so: inspection by the contractor, by the owner or by an independent third party. The hold points and records stay the same.