Why use the ROOFBOX® system to weather flat roof service penetrations?

Many buildings nowadays are designed with a usable flat roof area, and it is common practice to use this space for services equipment such as air handling units, fans, condensers, etc. 

This gives rise to the need to pass various pipes, ducts and cables through the flat roof system. Traditionally, the industry approach to weathering services penetrations like this involves some form of ad-hoc site-formed solution, with detailing often unprescribed and left open to the installer to devise. 

Failing to prescribe a proper weathering method at riser opening and service penetrations is really failing to plan or planning to fail. The problem with the ad-hoc approach is that it can often lead to poor quality sealing-up details, outside of warranty at the most vulnerable point on the roof! This in turn increases the chances of a dreaded roof leak at the service penetrations position. The line of responsibility might look something like this; 

1. No prescribed weather solution at the riser heads

2. Not included in the tender package

3. Not included in contractor prices 

4. Not considered at construction stage

5. Weathering around service penetrations undertaken at the last minute, with no budget & outside of any warranty

With this in mind, when approaching the design of a roof penetrations, there are some important matters to consider:

1. Space 

Services, (especially ductwork), need space, and sometimes there is a contest on for this on the roofIt’s important that the spatial arrangements on the roof are properly coordinated, and that space is planned in for all the required elements including plant screens, mechanical equipment, solar panels, walkways, services, upstands, etc, etc. 

2. Buildability 

It’s also important to make sure that the chosen service weathering system (including the final seal position to any pipe, duct or cable) is accessible and buildableIf a sealing-up detail can’t even be physically reached by an operative, it’s unlikely that a robust weathering detail will be achieved. 

3. Interfaces

Roof penetrations will almost always require an appropriate upstand detail to integrate with the roofing system on the project. Also, don’t forget to consider if there are additional elements adjacent to any of the risers (e.g. lift over runs, parapets, wall abutments, etc) these will also require a workable interface detail. 

4. Structural integrity 

It is critical to ensure that any structure (aka dog box, roof kennel etc) that is built to weather the services is structurally adequate and to resist the loading conditions that occur such as self-load, wind, snow – even a potential human. 

5. Thermal insulation 

Be sure to give consideration to the possibility of condensation to the internal of any closure over the risers. In addition, there is a need to make sure that u-value of closure element over a riser, fits into the overall roof u-value calculation.  

6. Material combustibility 

If the buildings design strategy prohibits the use of combustible materials, this needs to be duly reflected in the material choice used to create a weathering solution. 

 

7. Future access

Consider if there will be any need for service penetrations to be made at a future time, e.g. for later phases of works or tenant risers. Will it be possible to retro-add these to the riser top solution. 

8. Durability 

As an integral part of the building envelope, it’s important that the material finish of the system can properly endure the elements over a prolonged period of time.  It will need to resist corrosion, U.V., falling and driving rain, snow, wind, ice, heat, cold and any local adverse atmospheric conditions! 

9. Sustainability 

Due consideration must be given to the sustainability of any chosen method, including management of resources to reduce the carbon footprint of the building in operation. 

10. Aesthetic

Last but not least, don’t forget the overall form, appearance and colour.

ROOFBOX - Roof Cabinets

So how can the proprietary ROOFBOX® system help with these various aspects?

1. ROOFBOX® is a proprietary system designed for this particular area of the built environment, i.e. at positions where services penetrate a flat roof. This means that standard ROOFBOX® processes and methodology can be introduced to a project at an early stage of design, and a dedicated product solution can be developed and tailored to suit the needs of that particular project, using a standard ROOFBOX® system. 

2. Coordination tools are provided, (including guidance notes and parametric revit objects), to assist any design team to coordinate service penetrations with a dedicated weathering housing in good time, in context with the overall roof layout.

3. A planned and collaborative approach ensures that all ducts and service penetrations are configured to be ‘weatherable’ and can ultimately be weathered with a proprietary weathering housing.

4. As a proprietary system, up-front product design measures have already been undertaken with the ROOFBOX® product, to design out common industry weathering pitfalls. In addition, product-specific thermal and structural calculations have been undertaken to establish the respective parameters of the product, in terms of u-values and permissible sizes.

5. The ROOFBOX® system is time-served and tested and has been successfully utilised by many project teams over many years. The value of this experience is further augmented by third-party weather-testing and air-testing of ROOFBOX® flashings, lids and roof panels. ROOFBOX® products are covered by a NICHOLSON® warranty 

6. Where roof penetrations are planned for some time in the future, ROOFBOX® products are designed so that an appropriately flexible provision can be incorporated into the solution, in readiness.

7. Any ROOFBOX® project solution is supported by a dedicated technical team to undertake a project-specific review which looks at the buildability and ensures that the products and details proposed align with the overall build strategy.

8. The ROOFBOX® system uses a polyester powder coated in aluminium outer weathering skin to create an enduring surface that can stand the test of time to resist the elements. Should the building ever be re-purposed in decades to come, it should be noted that aluminium is a fully recyclable material.

9. ROOFBOX® has an environmental strategy with a primary benefit aimed at eliminating the significant environmental impact that invariably occurs following a roof leak. Secondary environmental benefits to a building include the ROOFBOX®‘s ability to prevent excessive heat loss or air loss, ultimately reducing the buildings carbon in operation. As an off-site manufacture system manufactured in the UK, there are also tertiary environmental benefits relating to material efficiency, minimising waste, avoiding offcuts and reducing transportation.

10. The ROOFBOX® has a pleasing aesthetic and can be finished in any RAL colour to match the roof scape.

Considering everything that’s involved to facilitate a robust weathering detail for service penetrations at roof level, the ROOFBOX® system is not a low-cost, quick-fire solution.  

However, ROOFBOX® products do offer the building owner, specifier and contractor a proprietary product that is safe, cost-effective, properly designed and provides a proven and warranted long-term solution to this scenario.  

To recap, the ROOFBOX investment unlocks the ability to overcome the challenges incumbent to creating flat roof service penetrations, and enables enduring weathering systems over riser positions that eliminate the pain and expense of roof leaks and the consequent damage to property and contents. This is an investment that has clear and tangible returns for everyone & by comparison the line of responsibility is defined from the start. 

No prescribed weathering solutions

1. No prescribed weather solution at the riser head at design stage

2. Nothing included in the tender package

3. Not included in contractor prices

4. Not considered at construction stage

5. Weathering around service penetrations undertaken at the last minute, with no budget & outside of any warranty

6. Potential leaks resulting in damage and costs. Dissatisfied stakeholders

Proprietary weathering solution specified

1. Considered & prescribed weathering solution at design stage

2. Solution included in tender package

3. Provision included in contractor quotation

4. Considered at construction and allowance for detailing made

5. Weathering to services provided for in a timely, tested and proven methodology

6. A secure long term solution with satisfied stakeholders

roof cabinets

The ROOFBOX® weathering system for service penetrations provides a proprietary and guaranteed solution to the inherent problems associated with bringing pipes, cables and ducts through the waterproofing layer at roof level. These insulated aluminium units are powder coated and provide an alternative to the traditional ‘dog kennel’ approach to weathering services as they exit onto the roof.

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