SKU: ade58b09b794 Category: CONSUMABLES Tags: chalk, chalk line, roofing chalk

Chalk Flask Red

Name: Chalk Flask Red
SKU: ade58b09b794
Availability: InStock

The Reclaimed Co. Price:

£7.20 + Vat

3 in stock (can be backordered)

🚚 Delivery
🏪 Collection

Delivery calculated at checkout and can be delivered nationwide by pallet/courier or locally by our own fleet

Your nearest store:

York

Sutton Road, Wigginton, YO32 2RB

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used to mark straight lines and measurements on roof
The bright red color stands out
Ideal for setting out leadwork, tiles, and general roofing layouts.
Nationwide delivery available
Collection available

+Product Info

Description

Chalk Flask Red

Chalk Flask Red (250g) is a must-have for roofers, used to mark straight lines and measurements on roofs before cutting or fitting materials.

It’s commonly used with a chalk line reel to create clear, visible guides on lead, tiles, and other surfaces.

The bright red color stands out, making marking quick and precise.

Ideal for setting out leadwork, tiles, and general roofing layouts.

Find more roofing supplies here

Have a look at some roofing work here by GNR

Additional information

Weight	2 kg

Slate Calculator

Slating Headlap

Lap

Expandable Headlap Info

Choosing Headlap

Definition: The vertical overlap between successive rows of tiles to prevent water ingress.

Factors to consider:

Roof pitch: Shallower pitches (< 30°) need 75–100 mm; steeper (> 45°) can use 50 mm.
Climate & exposure: Wind-driven rain or heavy rainfall zones benefit from more headlap.
Tile profile: Deeper tiles may require extra overlap to seal correctly.

Rule of thumb:

Standard (30–45°): 50–75 mm
Low (< 30°): 75–100 mm
High (> 45°): 50 mm

Slate Size / Type

Slate 50mm Lap

Selecting Tile Size

Coverage per tile: Larger tiles cover more area but are heavier, affecting handling and substrate load.

Aesthetic scale: Big tiles suit modern, minimal lines on large roofs; smaller tiles give more texture and a traditional look.

Structural limits: Check rafters and battens can support the chosen tile’s weight and fixing centres.

Installation speed vs. waste: Larger tiles lay faster but may require more cutting at edges, increasing waste. Smaller tiles take longer but can reduce off-cuts.

Compatibility: Ensure the tile size works with your chosen headlap & side-lap for correct coverage per m².

By balancing pitch, weather, substrate capacity and appearance, you’ll pick the optimal tile size for performance and style.

Slate 75mm Lap

Selecting Tile Size

Coverage per tile: Larger tiles cover more area but are heavier, affecting handling and substrate load.

Aesthetic scale: Big tiles suit modern, minimal lines on large roofs; smaller tiles give more texture and a traditional look.

Structural limits: Check rafters and battens can support the chosen tile’s weight and fixing centres.

Installation speed vs. waste: Larger tiles lay faster but may require more cutting at edges, increasing waste. Smaller tiles take longer but can reduce off-cuts.

Compatibility: Ensure the tile size works with your chosen headlap & side-lap for correct coverage per m².

By balancing pitch, weather, substrate capacity and appearance, you’ll pick the optimal tile size for performance and style.

Slate 100mm Lap

Selecting Tile Size

Coverage per tile: Larger tiles cover more area but are heavier, affecting handling and substrate load.

Aesthetic scale: Big tiles suit modern, minimal lines on large roofs; smaller tiles give more texture and a traditional look.

Structural limits: Check rafters and battens can support the chosen tile’s weight and fixing centres.

Installation speed vs. waste: Larger tiles lay faster but may require more cutting at edges, increasing waste. Smaller tiles take longer but can reduce off-cuts.

Compatibility: Ensure the tile size works with your chosen headlap & side-lap for correct coverage per m².

By balancing pitch, weather, substrate capacity and appearance, you’ll pick the optimal tile size for performance and style.

Slates Per m2

Expandable Slates per m² Info

Calculating Slates per m²

Definition: Number of slates needed to cover one square metre.

Formula: 1 000 000 mm² ÷ (effective width × effective height)

Where:

Effective width = tile width – side lap
Effective height = tile height – head lap

Example: 610 mm × 355 mm tile, 20 mm side lap, 75 mm head lap:

Effective width: 610 − 20 = 590 mm
Effective height: 355 − 75 = 280 mm
Area per slate: 590 × 280 = 165 200 mm²
Slates per m²: 1 000 000 ÷ 165 200 ≈ 6.05

Adjust your headlap and sidelap values for precise coverage calculations.

Slate Required(Required)

Measure Your Roof Area

Determining Your Roof’s Area (m²) Accurately measuring your roof is essential to estimate how much slate you’ll need. Follow these steps: Measure the rafter length Runs from the gutter up to the ridge line.

Width (m)

Length (m)

Total Mtr²

Total Slates Required

Copper Nails Total KG

Expandable Copper Nails Info

Copper Nails for Slating: Overview & Specs

Why use copper nails?

Corrosion resistance: Forms a protective patina to prevent rust and staining.
Superior durability: Lasts for decades without needing replacement.
Optimal flexibility: Absorbs roof movement without cracking or shearing.
Aesthetic harmony: Weathers to a warm patina that complements natural slate.
Chemical compatibility: No galvanic reaction with slate or lead flashings.

Packaging & usage: