SERPLYWOOD · CORE GUIDE
GUIDE 10 · CLIMATE & FIELD CONDITIONS
Summer & Winter Formwork Management: Thermal Dilation & Weather Guidelines
Author: İdris YAĞMAHAN / Mimar (Architect)
Published: 20/03/2026
Read Time: 9 minutes
Category: Climate & Field Management
Quick Technical Specification
Verified Engineering Specs
Thermal Expansion
α ≈ 1.1 – 1.3 × 10⁻⁴ K⁻¹
Linear Thermal Expansion
Expansion Gap
1.5 – 2.0 mm perimeter expansion gap during summer pours
Düşük Sıcaklık Sınırı
Impact-tough and ductile down to -20°C sub-zero conditions
Yüksek Sıcaklık Sınırı
Deformation-free steam curing endurance up to +75°C
UV & Güneş Dayanımı
UV-stabilized resin for open-air yard and jobsite storage
İstifleme Standardı
Store horizontally on flat ground with minimum 3 support bearers
Table of Contents
1. Thermal Physics of Polypropylene Shuttering
Unlike timber which swells irreversibly from moisture absorption, polymers exhibit predictable linear thermal expansion (α ≈ 1.2 × 10⁻⁴ K⁻¹). On a 2500 mm sheet, a 25°C temperature rise produces approximately 1.8–2.1 mm of elongation.
2. Summer Pouring Rule: 1.5–2.0 mm Expansion Joint
During hot summer installations, crew members must leave a 1.5 to 2.0 mm joint gap between adjacent sheet edges, sealed over with adhesive formwork tape. This prevents compressive buckling when sheets expand under direct afternoon solar radiation.
3. Sub-Zero Impact Toughness (-15°C)
SerPlywood panels are formulated with specialized block copolymer resin that prevents cold embrittlement down to -20°C. Concrete vibrators and corner drops do not shatter or split the material, even in severe sub-zero winter concreting.
Request On-Site Thermal & Handling Protocol
Equip your formwork foremen with our illustrated weather and joint handling reference poster.
Frequently Asked Questions about Thermal Dilation
Frequently Asked Questions
Common questions regarding board selection, reuse cycles, technical parameters, and global delivery.
Which is better, PP or PVC boards?
The polymer name alone is not a sufficient selection criterion. Internal cross-section (solid, honeycomb, or fluted), weight, test certificates, jobsite temperature ranges, and pricing must all be evaluated together.
Is plastic-coated plywood completely plastic?
Not always. Some hybrid products have a timber/plywood core with a plastic film or overlay. The core material and the surface must be evaluated separately. SerPlywood provides homogeneous solid/cellular polymer boards.
What should the support joist spacing be?
There is no single support spacing applicable to all polymer boards. It must be determined from the manufacturer load-deflection tables and permissible deflection limits (e.g. L/500) for the specific concrete slab thickness.
Can nails and screws be used on polymer formwork boards?
Yes, standard framing nails, screws, and formwork clamp fixings can be applied. The polymer structure grips fasteners securely and does not splinter, split, or delaminate after repeated fastening.
Can damaged polymer boards be repaired on site?
Yes, surface gouges, deep scratches, or accidental drill holes can be easily repaired using hot-air polymer welding, welding rods, or polyurethane plugs, restoring a flush surface.
Does a small sample piece reflect the full board performance?
Small hand samples are ideal for evaluating material density, surface finish, hardness, and waterproofing; full-span deflection and framing behaviors should be observed in actual site mock-ups.
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