Download - Open Web Joists. Product Overview What is an Open Web Joist? In Essence they are Warren Girders Manufactured from TR26 Grade Truss Timber & Steel Webs.

Open Web JoistsOpen Web Joists

Open Web JoistsOpen Web Joists

Product Overview

What is an Open Web Joist?What is an Open Web Joist?

In Essence they are Warren GirdersManufactured from

TR26 Grade Truss Timber &

Steel Webs

Common QuestionsCommon Questions

• What depths do they come in?

DepthsDepths

Strut Size Overall Depth

Gap Depth

PS8 202mm 108mm

PS9N 225mm 131mm

PS10N 254mm 160mm

PS12 302mm 208mm

PS14N 373mm 279mm

PS16N 421mm 327mm

HoweverHoweverThere are also a number of factors to consider here, like

span, centres, flange width and loading conditions. Beams may also be on edge

With 47mm timber on flat, there are 6 sizes of web / joist


• What depths do they come in?• How are they made?

Strut RunnerStrut Runner

Joists can also be made on a normal truss press but there may be problems restraining the top edge of the timber using standard truss clamps


• What depths do they come in?• How are they made?• What width flanges to they have?

Flange WidthsFlange Widths

• 47mm on edge• 72mm - 147mm on flat• Maximum 4ply on edge• Maximum 2 ply on flat (Up to 294mm)

On a standard run of joists you ideally want the flange width to be 72mm or 97mm on flat.

Maximum recommended chords on edge are 97mm


• What depths do they come in?• How are they made?• What width flanges to they have?• How do they compare in price to

solid timber and I-Joists?Singly, they may be a little more expensive.

HoweveHoweverrand fit

quickerSpan further…

They Give better access for services

RESULTThe overall job is

cheaper

Benefits of Open Web JoistBenefits of Open Web Joist

• Access for services

Access for ServicesAccess for Services

Note soil pipe next

to the bearing

Access for ServicesAccess for Services


• Access for services• Larger spans than cut timber & I-

Joist

I-Joist Span TablesI-Joist Span Tables

241 deep, Series 550 Joist @ Rating 45 Spans 4.3m

Open Web Joist SpansOpen Web Joist Spans

254 deep PS10N Spans 5.14m – That’s 0.84m more

Open Web Joist SpansOpen Web Joist Spans

• Based on 400mm centres and standard loads

72mm 97mm 122mm 147mm

PS 8 4880 5210 5480 5695

PS 9N 5100 5430 5685 5900

PS 10N 5520 5880 6160 6400

PS 12 6330 6760 7120 7410



Joist• Inherently stable – faster assembly, minimal

bracing

I-Joist Bracing RequirementsI-Joist Bracing Requirements

Open Web Joist Bracing RequirementsOpen Web Joist Bracing Requirements




bracing

• Light weight




bracing

• Light weight• Rigid design – easier manual handling than I-

Joist




bracing

• Light weight• Rigid design – easier manual handling than I-Joist

• Squeak free – cross grain shrinkage is minimal


• Access for services• Larger spans than cut timber & I-Joist• Inherently stable – faster assembly, minimal bracing

• Light weight• Rigid design – easier manual handling than I-Joist

• Squeak free – cross grain shrinkage is minimal

• Versatility

Open Web Joist VersatilityOpen Web Joist Versatility

TRIMMABLE TRIMMABLE ENDSENDS

TOP BEARINGTOP BEARING

Open Web Joist VersatilityOpen Web Joist Versatility

Trend towards Multi-Storey Trend towards Multi-Storey DwellingsDwellings

Open Web Joist Growth Since 1997Open Web Joist Growth Since 1997

19971998

19992000

20012002

2003