In this post we’ll explore SIPs, a modern high performance building system which is becoming an increasingly common method for construction across the globe due to its simplicity in construction and its many inherent benefits that create higher quality buildings.



What are SIPs?

Wood is the most widely used building material across the globe. It’s a sustainable material, flexible in design and easy to work with. Structurally Insulated Panels are an advanced form of timber construction. SIPs are a type of high performance building system used in residential, light-weight commercial, and even small industrial buildings. A SIP is made up of two structural OSB faces which both sandwich an insulating foam core as pictured below. SIPs are incredibly versatile and can be used to construct walls, floors, and even roofs which speeds up the construction process whilst delivering a higher quality of build in comparison to other traditionally used materials such as masonry.


A closer look at the SIPs construction system shows how the insulation is sandwiched between two large OSB3 boards to create a complete insulating and structural component.







Should I consider using SIPs in my project?

Due to the ever increasing carbon footprint of the construction industry, the UK’s building regulations are becoming increasingly stringent. Part L of the building regulations focuses on the conservation of fuel and power as reducing carbon emissions for new build properties remains high on The Government's agenda, and plays a big part in the design and construction of new build properties. SIPs are in a league of their own when it comes to meeting these stringent guidelines. The sheer thickness and continuous line of insulation sandwiched within the structure of a SIPs building leads to a very energy efficient and comfortable internal environment. The carbon footprint of a SIP building is reduced immensely as energy demand is significantly reduced leading to a more economical and environmentally friendly building in the long run.

This detail shows how the various materials would come togther along with the continuous line of insulation in the interior to increase overall u-values

The benefits of using SIPs

As SIPs are made in a factory environment and to specified shapes and sizes, there is minimal waste in comparison to traditional construction materials. The speed in which a SIPs building can be erected equates to labour savings from shorter construction times and the prefabricated nature of this system can effectively make this building method financially more viable than other traditional construction materials. This is particularly attractive for self-builders, where the ability to erect the structure quickly and make it watertight means that an element of self-finish can be completed by the client, or other contractors.

Further savings occur as the need for heating and cooling systems are drastically reduced due to the thermal characteristics and airtightness of this technology. The inherent air tightness of SIPs necessitates in the need to integrate an air exchange system such as a Mechanical Ventilation Heat Recovery system (MVHR) to exchange stale air for clean fresh air as touched on in our previous posts on Airtightness This allows for a controlled internal environment which is especially beneficial, in combination with air filters, for those with allergies. This topic will be explored in detail in a future post on Mechanical Ventilation.


What about the external/internal finish of a SIP building?

As the name suggests, SIPs are generally used for their inherent structural properties but can also be used with other structures to form an insulation and airtight layer to a building. A SIPs structure can be clad in a variety of different materials depending on the desired aesthetic. Brick work is often used as the exterior face to fit the local context of many UK cities. Timber cladding, render boards, metal cladding amongst many other options are available as the finished structure is easy to apply finishes to. The interior can be finished with plasterboard or plywood, again depending on the desired aesthetic.


We explored using SIPs on our project at Glebe barn, due to the speed of construction and the possibility of incorporating an element of self-build. For the exterior finish, ideas of vertical timber boards meeting the stone plinth looked like a great juxtaposition of materials and expressed the modernity of the new build whilst honouring the material palette of the existing barn. The conceptual 3D technical details above and below show how the construction would come together on site as well as some thoughts on the interior and exterior finishes mentioned earlier.

This conceptual detail shows the exterior finish we are trying to achieve and how the timber cladding would meet the stone wall.



If you are interested learning more about SIPs, or have a project in mind where you are considering using this method of construction, then please do get in touch.



Updated: Jul 6


Earlier this month we gained planning consent for a new single storey extension to a previously converted threshing barn in North Devon.


The design incorporates strategies for sustainability, aiming to reduce energy consumption during construction and throughout the lifetime of the building. We have decided to use materials with a low embodied energy: the structure will be timber framed, clad with lime rendered wood fibre boards and locally sourced timber cladding. We are also looking to specify insulation levels which are better than the minimum required for building regulations, so as to improve the performance of the building for years to come.


We are looking forward to developing the detailed design as we work towards getting the project on site.


Learn more about my other residential and eco projects.

Updated: Jul 27

Since the Covid 19 pandemic, many businesses have needed to adapt to new ways of working, in order to meet government legislation and ensure that customers remain safe and healthy when they undertake essential work. This process of change has led to new discoveries and ways of working which are likely to remain well after the pandemic is over. I thought I would share a few changes I have made to my practice in the last 3 months.


More collaborative working


Virtual meetings have become a new phenomenon, and they have proved to be very effective both in terms of meeting up with clients on a more regular basis, and collaborating with other members of the design team, for example structural engineers, where previously a pre-planned and long distance journey might be required. It is no longer necessary to crowd around one computer or set of printed drawings to discuss the project. Instead the project information can be shared with the group to be viewed together.


Improved visualisations for clients


The challenge for most projects is to help the client visualise how the design will look in real life, both during the design process and before construction when the design is finished. I prepare most of my designs on a 3D modelling software called Revit, and I have discovered that it is possible to share this model with clients so that they are able to view the design from their own computer or on their tablet as it develops. It is possible to “walk-through” building, export views and comment on parts of the design which need changing.



Also during the lock-down I have been improving my 3D rendering skills using an external software package called Blender. This allows my basic model to produce photo-realistic images of the interior and exterior of the building, incorporating realistic lighting, materials and textures to take the design visualisations to the next level.



Glebe barn render

Leigh cottage render


Safe site visits


I now keep site meetings to an absolute minimum, but sometimes they are essential to ensure that the design progresses in an effective manner. At the beginning of jobs I always undertake a measured site survey to analyse the site and gather information about any project, but careful planning is required to make sure this is as safe for all of us. Before the visit I will coordinate with the client about the planned measure-up to discuss how we will ensure social distancing measures and the steps taken to disinfect tools and equipment. The measure-up will be postponed if either party is isolating, shielding or simply does not feel comfortable with it at that moment in time.


Rather than meeting all new potential clients on site, as a first step I will now be arranging virtual meetings to discuss all possible new jobs. During this meetup I will try to gather as much information as possible for me to prepare a quote for the work, so we will discuss information about the site and the client's requirements for the project. There is no obligation to proceed any further than an initial meeting, so if you are unsure about whether you need assistance form an architect, please do not hesitate to get in touch.

Your local architects in Bristol, Devon and SW