# Johnstone's Trade Aqua Guard Primer Undercoat

Primer, undercoat and sealer · Johnstone's Trade

Johnstone's Trade Aqua Guard Primer Undercoat covers about 13 m² a litre, by Johnstone's Trade's own figures.
Source: Johnstone's Trade, Johnstone's Trade Aqua Guard Primer Undercoat data sheet, read 11 October 2026.

Johnstone's Trade gives no single number of coats for it in the document read for this page.

What it is for, in the maker's words: “Johnstone’s Trade Aqua Guard Primer Undercoat is an innovative, water-based primer and undercoat that is ideal for interior wood” (Johnstone's Trade Aqua Guard Primer Undercoat product page, read 11 October 2026).

## Coverage

Johnstone's Trade states about 13 m² a litre. The maker's words: “Johnstone’s Trade Aqua Guard Primer Undercoat will cover approximately 13m2/l depending on the nature and porosity of the surface being painted”.
- Bare, rough or absorbent surfaces: A maker's coverage is their best case, on a smooth sealed surface: bare, rough or absorbent surfaces take more. Johnstone's Trade's own words: “Johnstone’s Trade Aqua Guard Primer Undercoat will cover approximately 13m2/l depending on the nature and porosity of the surface being painted”.
- Waste and touch-ups: The tin-by-tin figures add nothing for what stays in the tray and on the brush, or for touching up.

## Coats

The document read for this page gives no number of coats for Johnstone's Trade Aqua Guard Primer Undercoat. Follow the tin's own instructions.

## Tin sizes

| Tin | One coat | Two coats |
|---|---|---|
| 1 L | about 13 m² | about 6.5 m² |
| 2.5 L | about 32.5 m² | about 16.25 m² |
| 5 L | about 65 m² | about 32.5 m² |

Arithmetic on the maker's figure: the litres in the tin times the coverage per litre, with nothing added for waste.

## Where to buy it

The page has the shops' own searches for it, and any link there that is paid for is marked Ad: https://buildbatch.co.uk/products/johnstones-trade-aqua-guard-primer-undercoat/#where-to-buy. BuildBatch sells nothing and compares no prices.

## Questions

**How much does a litre of Johnstone's Trade Aqua Guard Primer Undercoat cover?** Johnstone's Trade states about 13 m² a litre for Johnstone's Trade Aqua Guard Primer Undercoat (Johnstone's Trade Aqua Guard Primer Undercoat data sheet, read 11 October 2026). A maker's coverage is their best case, on a smooth sealed surface.

**How much does a 5 litre tin of Johnstone's Trade Aqua Guard Primer Undercoat cover?** At the maker's figure a 5 L tin covers about 65 m² in one coat, or about 32.5 m² in two coats. That is the litres times the coverage per litre, with nothing added for waste.

**How many coats does Johnstone's Trade Aqua Guard Primer Undercoat need?** The document read for this page gives no number of coats for Johnstone's Trade Aqua Guard Primer Undercoat. Follow the tin's own instructions.

**What is Johnstone's Trade Aqua Guard Primer Undercoat for?** Johnstone's Trade says: “Johnstone’s Trade Aqua Guard Primer Undercoat is an innovative, water-based primer and undercoat that is ideal for interior wood” (Johnstone's Trade Aqua Guard Primer Undercoat product page, read 11 October 2026).

**What tin sizes does Johnstone's Trade Aqua Guard Primer Undercoat come in?** The catalogue lists 1 L, 2.5 L and 5 L. A shop may not stock every size.

## Where the figures come from

- Johnstone's Trade, Johnstone's Trade Aqua Guard Primer Undercoat data sheet (https://dam-cdn.ppg.com/adaptivemedia/rendition?id=a5510292ca0a4010901f6c7511a2ce0e98b56167): coverage, read 11 October 2026.
- Johnstone's Trade, Johnstone's Trade Aqua Guard Primer Undercoat product page (https://www.johnstonestrade.com/en-GB/product/aqua-guard-primer-undercoat/17000DUT087): what it is for, read 11 October 2026.

Written with AI tools; not yet checked by a tradesperson. Follow the tin's own instructions.

The page: https://buildbatch.co.uk/products/johnstones-trade-aqua-guard-primer-undercoat/