Buxton & Leek College Engineering Building – the design process


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The Buxton & Leek College Engineering Building is a new-build educational facility currently being erected on site at the edge of the Peak District. The building is a split-level hybrid construction utilising steel, concrete, cross-laminated timber and glulam materials.

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With foundation works completed on site, focus now turns to the erection of the visually-exposed solid timber superstructure that will form the heart of the new learning environment.

The project represented a unique opportunity for TimberFirst to demonstrate steel, glulam, CLT design and fabrication drawing expertise. Our role was to complete the final structural design of the superstructure – coordinating with the

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design team to ensure the design brief was met – and subsequently to provide Constructional Timber with the full documentation necessary to procure all elements for construction. This information included all fabrication drawings for the CLT, glulam and steel elements, a fixings take-off for all connection items, and site drawings to enable swift and safe erection on site.

LCE-PH-CT-1618The finished building is designed to achieve a BREEAM ‘Excellent’ rating, with sustainability at the core of the design. The visually-exposed timber panels and beams will also provide an excellent teaching environment for Leek College.

Design considerations encompassed site access constraints, fire (charring) analysis, delivery sequencing to suit erection methodology, exposed connections and services coordination. Working in conjunction with Hunt Architects, Engenuiti and Constructional Timber, the design challenges were rapidly solved and the ambitious six week design and fabrication information

programme was met on time by the TimberFirst team. The fabrication drawings were then used by Constructional Timber to procure and fabricate the elements for construction.

TimberFirst is proud to have been involved with this challenging and inspiring project.

Tim Butler, Senior Structural Engineer

‘London – the forest has come to the garden city’ Talk and City Tour


Magda our Senior Designer spent her Sunday promoting the benefits of solid timber construction and how it is a pro-ecological solution for developments in highly urbanized environment.

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As part of a study trip organised by the University of Economics Katowice, International University of Sarajevo and TOBB University of Economics and Technology Ankara, the students spent 7 day in London discussing whether economic and cultural sustainability should be central to the growth of today’s cities.

Magda’s workshop and city tour focused on how in London the forest has come to the garden city and that in light of the current global trends such as extremely fast growing population and the increasing shortage of natural resources (including fresh water) the design of our cities need to respond to this.  We believe that as our ‘new cities’ become denser, greener and taller,  the materials used to build them need to be renewable, stronger and lighter as well as environmentally friendly and less water demanding.

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Photo: Whitmore Road

Magda talked about how the Government was responding to these future demands by introducing policies to prescribe sustainable developments (London Plan policy 5.3 – Sustainable design and construction) and how solid timber construction ticks all the boxes and provides additional benefits in the urban context, including:

  • Lower on-site storage requirements compared to other materials
  • Responds to Cities’ ‘Over and under the ground’ challenges (structurally lighter it can be built over sewers, metro tunnels and other underground infrastructure
  • Seldom requires a tower crane – no additional foundations required on sites with demanding underground conditions, it shortens site preparation time
  • Ideal for dense neighbourhoods – less dust, vibration, noise and obstructions (no propping), thus reducing the impact of construction and disruption to neighbours
  • Fewer operatives on site and for a reduced period of time
  • Low site traffic – reduces the deliveries to site compared to reinforced concrete, up to 7.5 times less

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Photo: Bridport House

The students loved Magda’s talk and were fascinated by the city tour of Bridport House, Whitmore Road, Stadthaus and WoodBlock House – Hackney’s  four solid timber residential buildings.

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Photo: WoodBlock House

For more information on Magda’s talk and city tour email marketing@timberfirst.com.

WoodBlock House CLT superstructure completes on site


The cross-laminated timber superstructure for WoodBlock House, the new studio and residence of artist Richard Woods, is completed on site.

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Designed by dRMM, the new build in London promotes the use of timber to form distinct boxes reflecting the different functions inside, and deliberately refers to the powerful printing technique for which the artist is internationally renowned.

SAMSUNG DIGITAL CAMERASAMSUNG DIGITAL CAMERAThe project is TimberFirst’s inaugural building design project in the UK.  Matthew Linegar, Technical Sales Director said ‘we are very proud to be involved in such a unique project, working with an artist of Richard’s caliber and passion for timber has been a privilege

We have loved working with dRMM on the delivery of their creative vision and aspirations for the project, and are delighted to see the superstructure completed on site.’ 

TimberFirst undertook the structural design of both the timber superstructure and the concrete sub structures from RIBA stage C on behalf of the Client.

The CLT structure was supplied and installed by Metsä Wood and took 10 days to build. Cape Construction are the main contractor.

To see more photographs of WoodBlock House visit our Facebook page WoodBlock House album

Technical Blog Series – Wood burns, so what?


In our technical blog series we will be addressing the issues that are considered barriers to the use of solid timber as a modern method of construction.  We will begin with fire, as it is the most commonly asked question.  Read our Technical Director Matt’s blog which discusses the issues around solid timber construction and fire.

Wood burns, so what?

One of the biggest concerns for designers, clients and end users when using solid timber for building structures is fire.  Often people’s preconception of the performance of timber in fire is misconceived but perhaps this is reasonable, after all timber does burn!

To successfully implement a solid timber building you must first understand how timber burns and it is within the how that solid timber construction really comes into to its own – in terms of fire performance when compared to other traditional constructional materials and can even outperform them despite timbers relative combustibility.

There are several recent examples of catastrophic fires of timber framed construction which is particularly vulnerable during the construction phase.  The significant media coverage these events have received has only served to reinforce people’s misconceptions.  However, solid timber construction performs very differently to timber framed construction both during the construction phase and in the as built situation. This is primarily due to the difference in combustibility of the two construction types.  But they are both made of wood and wood burns?  The difference is that the combustibility of timber is directly proportional to ratio of surface area to volume. 

Timber framed construction has a high surface area to volume ratio whereas solid timber construction such as CLT has a relatively low ratio. By way of a simple example try to imagine yourself lighting a pile of logs with a box of matches, its virtual impossible.  Now imagine trying to light some kindling (small pieces of wood), these readily ignite and then the increased heat and fuel eventually ignites the logs.  This is because the kindling has a high surface area to volume ratio whereas the logs have a low ratio, similar in fact to timber frame construction versus solid timber construction.  This shows that given sufficient heat, oxygen and fuel solid timber will burn, so we must design solid timber structures in such a way to limit the opportunity of combustion and also to understand how it burns.

Key stages of a fire

  1. Developing fire – a) Incipient – once combustion begins, development of an incipient fire is largely dependent on the characteristics of the fire compartment and the fuel involved.  b) Growth – provided there is adequate oxygen to continue fire development during this initial phase, radiant heat warms adjacent fuel and continues the process of pyrolysis.
  2. Flashover – flashover is the sudden transition from a growth stage to fully developed fire. When flashover occurs, there is a rapid transition to a state of total surface involvement of all combustible material within the compartment.  The temperature at which flashover occurs is largely dependent on the conditions of the compartment but typically temperatures of between 500 to 600 degrees are required.  Note – it is important to remember that flashover does not always occur. There must be sufficient fuel and oxygen for the fire to reach flashover.
  3. Fully developed fire – the compartment temperatures of a developed fire are normally in the range of 700 to 1200 degrees. It should be noted that in the UK most fires are extinguished either before or during the developed stage of a fire.
  4. Decay – the decay stage is characterised by a significant decrease in oxygen or fuel, putting 
  5. an end to the fire.

Performance of fire

How does solid timber burn?

Although timber is combustible, solid timber is not readily ignited and there are few recorded cases where timber will have been the first material to ignite.  Solid timber construction will require surface temperatures well in excess of 400 degrees to ignite without a pilot flame.  Even in the presence of a pilot flame the surface temperature will have to be in excess of 300 degrees for a significant time before ignition occurs.  Therefore during construction careful consideration must be given to the use, and in particular the storage of, highly flammable substances that can provide the necessary heat to ignite timber.

When the surface of the solid timber does ignite it burns rapidly. The burned solid timber becomes a layer of char which loses all strength but retains a role as an insulating layer preventing excessive temperature rise in the core of the solid timber.  The thermal conductivity of the char layer is about one sixth that of the virgin solid timber.

The highly insulating char layer will cause a steep thermal gradient across the char layer. Underneath the char layer, there is a layer of heated solid timber with a temperature of above 200°C, which is known as the pyrolysis zone. This part of the solid timber is undergoing irreversible chemical decomposition caused solely by a rise in temperature and accompanied by loss of weight.

The inner core of the solid is slightly temperature affected with some loss of strength and stiffness properties, mainly due to the moisture evaporation in the wood. The charring rate is more or less constant and depends on the density and moisture content of the solid timber but is typically 0.7mm/min for softwood such as Spruce which is widely used for CLT and glulam.

Fire performance of solid timber

We have seen that the fire performance of solid timber is dependent on the charring rate and the loss in strength and modulus of elasticity.

To achieve the required design fire resistance period there must be sufficient virgin solid timber remaining behind the char layer to sustain the loads applied.  Therefore each solid timber element within a building structure must be designed for the required design fire resistance period and the specific loadings applied to that element.

The fire performance of solid timber can be further enhanced by the use of fire resistant claddings but the designer must be aware of the effects this approach on the solid timber as part of the overall system.

SOFIE Research Project – Fire Testing

SOFIE is a research project on sustainable buildings undertaken by IVALSA, an institute of the National Research Council of Italy, and supported by the Autonomous Province of Trento. The aim of SOFIE was to improve the construction system for multi-story wooden buildings which is characterised by low energy demand, high level of sound insulation, high durability and excellent fire and earthquake performance.  The research project included fire and earthquake testing.  To see how the multi-storey cross laminated timber structure performed in the fire test, watch this film provided to us by the SOFIE team.

For more information on SOFIE visit http://www.progettosofie.it/index_eng.html

Flitched – The Upcycler’s Design Competition and team LNP132’s design


Nick Nearchou, our Graduate Structural Engineer as part of team LNP132, entered the Flitched – Upcycler’s design competition, which invited designers to collaborate and design a poetic and useful structure for the Caravanserai community http://caravanserai.org.uk/ in Canning Town, East London.  The competition encouraged collaborative design using only recycled materials from local communities through the medium of flitching.  The winning design will be built on the Caravanserai site in East London.

Although LNP132 did not win the competition, they were one of nine teams short-listed for the finals and they felt that for them, the wider outcome was a new appreciation for the importance of design for the community, from the community.  Nick has written about his team’s approach and design – enjoy.

Workshop Garden – An Evolving Transitional Place

‘A Transitional Space for the Transitional Mind’

LNP132 team:

  • Nicholas Nearchou – TimberFirst
  • Lyn Poon – Architectural Assistant
  • Niri Arambepola – WSP Group

The Approach 

Recycling is a circular process, output informing input. This idea of cycles and transitions led the team to look into other natural and industrial transitions and cycles that inform our lives:  the carbon cycle, the rankine cycle, the water cycle, the building life cycle, the nitrogen cycle, the seasonal cycle and many more.

This led to the design a space which was transitional in function and flexible in use.

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The Design

The central point of the design was the fire around which these transitions could take place. We then decided we needed an open multi-functional workshop area which led the design of the plywood tree structures. An area for storing materials and a nursery for plants enclose the ends of the plan.

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 ‘Tree’ Structures

The slotted plywood ‘tree’ structures are structurally independent which allows flexibility in the plan layout and enables easy alterations later.  The ‘trees’ are easily reproducible allowing potential expansion.

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The ‘trees’ are primarily built up of slotted and screwed 18 mm plywood sheets. All flitching is achieved through screwed and nailed connections this simplifies fabrication and increases construction tolerance onsite which are both favourable from a constructability point of view.

Construction of the ‘trees’ does not require any heavy machinery or specialist equipment, fabrication is easily achievable through the use of basic equipment such as jigsaws and power drills. The fabrication stages are simple consisting of simple cutting, screwing and slotting procedures.

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The plywood cantilever arms are made up of double plywood sheets moment connected to the plywood columns using a circular arrangement of screws; this expresses the load transfer in the system. The solid timber rafters are screwed into the plywood arms at packer piece positions between the double arms; these packer pieces increase laterally rigidity reducing buckling effects. The plywood columns are made up of slotted plywood sheets which are screwed together for robustness using solid timber packer pieces. The plywood is already exterior grade plywood but to further enhance the structures durability thermo tape has been used along the plywood edges (the end grains) in order to prevent moisture ingress. The plywood columns are then screwed to equal angle girders at the base, these E.A. then continue down into the ground into a concrete shoe footing, the shoe shape prevents uplift and overturning from wind actions.

To see the team’s presentation, go to http://prezi.com/tevkqogzdqpw/flitched-iii/

Happy New Year from TimberFirst


2012 has been an exciting and interesting year for TimberFirst – we have been involved with great clients on pioneering and industry leading projects throughout the world.

During 2012 we continued to develop our knowledge and understanding of the global solid timber and construction markets; successfully delivered our first projects in the UK and Australia; redefined our offering and sharpened our profile to meet the needs of the global construction industry; developed our brand identity and strengthened the delivery of our services through the promotion of Tim Butler and Gregor Rossegger to Associate level.

We are really excited about 2013 and the opportunities for the development, use and application of solid timber in the global construction market.  We will remain at the forefront of the solid timber industry, with pioneering projects in the pipeline from around the world – UK, Europe, America and AsiaPacific.   Our new year’s resolution is to continue challenging, innovating and adapting – ourselves, our environment, the timber industry and the construction market; exploring potential and always thinking differently.

We will keep you updated with all our news over the coming year and are looking forward to launching our new website very soon.  If you have any projects or opportunities that you want to discuss give us a call on t: +44 (0) 203 176 4864 or email us at enquiries@timberfirst.com.

From everyone at TimberFirst we wish you a happy, healthy and prosperous 2013.

Seasons Greetings from TimberFirst


Seasons Greetings and best wishes for 2013 from everyone at TimberFirst