Introduction to Engineered Open Web Joists
easi-joist® is an engineered open web joist system from Wolf Systems Ltd, it is also commonly referred to as easi joist, easy joist, easyjoist, Posi-Joist™, posijoist, eco-joist, Ecojoist® or SpaceJoist™
E & H Baxendale Ltd have been manufacturing easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) since 2006 making us the most experienced easi-joist® manufacturer in Lancashire, if not the whole North West of England.
The easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) open web joist is a parallel chord truss utilising stress graded timber chords. These chords are plated together with a precision engineered and manufactured structural component called the metal web and, when combined, form the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®).
The easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) combines the lightness of timber with the structural qualities of metal. Together these two materials offer an opportunity for designing commercial, domestic and industrial floor and roof applications with spans equal to and exceeding traditional timber joists and there equivalent timber alternatives, but with better damping and stiffness qualities.
easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) is a precision designed and manufactured joist system, originally created to make floor joist manufacture faster, more cost effective and easier to install easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) is also commonly used as a flat or pitched roof joist, or as a stud in timber frame construction.
The timber used in the design of easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) is kiln dried and stress graded TR26, and complies with current European and British Standards.
The majority of easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) that E & H Baxendale Ltd supply use un-treated timber, if treated timber is a requirement for your project make sure to tell us that your project requires treated timber when requesting a quotation as timber treatment does incur a charge. Treated timber will be pressure impregnated with either PROTIM Aqeos or VACSOL Aqua which are both waterborne products containing biodegradable fungicides and insecticides.
- Features & Benefits
- easi-joist® Roofing
- easi-joist® Walls
- easi-joist® Sizes
- Support Conditions
easi-joist® FeaturesHave a look at an easi-joist floor in a 3D PDF.
- Factory manufactured, made to measure.
- Long continuous spans, reducing or eliminating the need for intermediate support walls.
- Light and easy to handle.
- Increased spacing centres.
- Dimensional stability.
- Design accuracy through specialist software.
- Trimmable ends to facilitate installation where bearing support is inconsistent.
- Wide nailing surface making the nailing and gluing of decking quicker and more accurate.
- Improved floor performance.
- Stiffness and strength built into the floors improving floor rigidity.
Open web design
This allows for easier, more practical, installation of services including waste water pipes, electrical cabling, heating pipes and other services. Also, no hole locating or drilling limits any possibility of incorrect workmanship and reduced labour costs.
The combination of smaller timber sections with the lightweight metal web means that the finished product is lighter than timber and much more lighter than timber equivalents.
Handling and installation
Large bearing surface allows a speedy set out of joists, improves joist stability when laying out joits and enables easier fixing of decking materials.
Reduced site wastage
The precision-manufactured easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) virtually eliminates all site alterations, and standard timber sizes ensure materials are readily available.
The reduced sections used in the manufacture of the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®), combined with the metal web mean that there is less loss of moisture and shrinkage, thus providing a quieter and longer lasting floor system.
Improved sound performance and reduced vibration
The metal web floor system allows for the installation of a rigid strongback that reduces vibration and improves the overall acoustic performance of the floor.
To supply easi-joist® in the UK and Ireland it was necessary to ensure the floor system meets the requirements of The Building Regulations. easi-joist® is recognised for use in floor construction by the NHBC (the standard setting body and leading warranty and insurance provider for new and newly converted homes in the UK) and Homebond in the Republic of Ireland (the organisation which since 1978 has enabled home builders to provide their customers with new home warranties and deposit and stage payments cover).
European Technical Approval (ETA) - Certificate No. ETA-07/0032
After exhaustive tests carried out by BMTRADA, on the 28th March 2007 easi-joist® became the first metal web floor system to attain ETA approval. Eurpean Technical Approval is basically an assesment of a product to make sure it is fit for its intended use within each European Member State; in this case, the assesment of easi-joist® for use within dometic, industrial or commercial buildings.
Irish Agrément Board - Certificate No. 07/0280
After satisfying the requirements of the IAB, on the 19th June 2007 easi-joist® became the first metal web joist system to be approved for supply in the Republic of Ireland. Irish Agrément Board Certificates establish proof that the certified products are 'proper materials' suitable for their intended use under Irish site conditions, and in accordance with the Building Regulations 1997 to 2006.
On the 24th May 2007 easi-joist® became the first metal web joist system to attain Robust Detail Approval (EFT3). This means that easi-joist® used in timber frame flats, constructed as per E-FT-3 will not require pre-completion sound testing to prove compliance with Part E of the Building Regulations in England & Wales; saving time, money and the uncertainty of pre-completion testing.
Flat Roof Structures
Primarily designed as a floor joist the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) system is also the ideal solution for creating flat roof structures as a lighter, more insulating alternative to solid sawn timber. Not only will easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) span the wallplates but by adding additional columns over the support points the easi-joist® can be cantilevered to provide an overhang that is no more than 1/3rd the internal span of the joist.
easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) flat roof joists have also been used in the construction of orangery roofs creating large openings supporting glazed units, where appropriate the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) can also be cantilevered to provide overhangs to form soffits.
Pitched Roof Structures
By redesigning the end column configuration, the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) system can be installed onto a wallplate or ridge beam without the need for a bevelled wallplate or special metalwork item. This versatile connection detail enables top and bottom supports to accommodate a range of bearing widths and can also incorporate intermediate supports.
Using easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) in this way creates a room in the roof much the same as using attic trusses does, but easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) has the advantage of the open web design which easily accommodates electrical, plumbing, waste water and other services which the attic truss can't do.
The two diagrams below show the typical ridge and eaves details of the easi-joist®.
easi-joist® Timber Frame
easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) can now be found in the construction of timber frame buildings, not just as a floor joist but as the walls as well. Using easi-joist® studs in timber frame construction has a number of benefits, firstly
In 2010 E & H Baxendale Ltd manufactured and supplied the easi-joist® and the trussed rafters that were used in the construction of Boar's Den Barn, it was received so well that nearly twelve months later another property was constructed on a neighbouring property again using easi-joist® walls and roof trussed rafters.
We have put together a few information sheets that show various construction details for easi-joist® stud walls, until the pdf copies are uploaded to the site for you to view and download I have put the images on the E & H Baxendale Ltd Flickr photostream
|H (mm)||W (mm)||W (mm)||W (mm)||W (mm)|
easi-joist® metal web joists are available in 5 different depths utilising 35mm or 47mm top and bottom timber chords and 4 different single-ply joist widths. Multi-ply joists are created by fastening joists together either on-site or in the factory utilising Cullen Timberlok or Simpson Strong-Tie SDS or SDW self-tapping coach screws.
Accommodation of Services
A significant advantage of the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) floor joist system is the space provided by the open metal web design allowing for the easy installation of electrical, plumbing, waste water and other services through the joist space providing real time saving.
Because the open web design of the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) system removes the laborious work needed for notching, drilling or cutting holes when using other joist systems the installation cost of services can be greatly reduced.
Furthermore, the curved edges of the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) webs and the absence of protruding plate edges removes any potential for damage when feeding through pipes and cables.
Along with traditional need to install ventilation services in bathrooms and kitchens, government initiatives for air tightness will require the installation of further mechanical systems for air exchange. The open web design provides an ideal zone for the passage of ducting for these devices.
UK easi-joist® Span Tables
The following span tables are to be used as a basic guide to achievable joist span for given depth and spacing, and should be used for estimating or feasibility only. Actual maximum joist span is dependent upon a number of conditions. The spans given have been designed using support condition SC2, bottom chord full with 100mm wide supports at each end.
Please note that the maximum spans shown above are only to be used as a basic guide. The actual maximum joist span will depend on the loadings, support conditions and bearing widths. Please note that our easi-joist® press has a manufacturing limit of around 8 metres, so even though the above table may show that a span of over 8 metres is possible it may not be possible for us to manufacture it.
easi-joist® Support Conditions
The support conditions, also known as end details, pictured below show the versatility and flexibility the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) system has for accommodating various methods of connection to timber frame, masonry walls, steel or timber beams. Because support conditions and web direction/orientation can affect the spanning capacity of a joist the support conditions shown here may not be suitable or possible for every joist design.
Of the easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) designed and manufactured by E & H Baxendale Ltd most have used support condition SC2, bottom chord full which is ideal for building into walls, SC1 with it's trimmable ends is most popular when used with joist hangers to provide some room for on site alterations incase walls don't run perfectly straight.
The one question everyone asks is how much does an easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) cost? well the answer is until we have designed it we don't know, we have a rough idea based on previous enquiries but given that easi-joist® (aka Posi-Joist™, SpaceJoist™, Ecojoist®) comes in many different lengths, widths, depths, internal web configurations, and end support conditions it would be a very, very long and complicated list.
The best way to find out how much the easi-joist® you require will cost is to use our online easi-joist® enquiry form which you can also access by clicking on the banner above or give us a call on 01257 791264 between 7:30am and 4:00pm Monday to Friday. Once we have received your enquiry we will put your joist into the Wolf Systems easi-joist® design program which will tell us what size joist and web configuration will work for your project, from that we can then give you the most accurate price possible.
Based in the village of Coppull in Lancashire located just off the A49 between Wigan and Preston, E & H Baxendale Ltd routinely deliver roof trusses and easi-joist throughout the North West of England extending from the Scottish borders in the north to the northern margins of the Midlands in the south covering Cheshire, Cumbria, Greater Manchester, Merseyside and Lancashire. Deliveries outside these areas are usually made by outside an outside haulier who will set the delivery price, it is for this reason that it is normally only cost effective to supply large projects outside the North West.