Precast Concrete Box Culverts

A Precast Concrete Box Culvert is an easily-installed conduit used to enclose small roads, pathways or flowing water (e.g. streams, stormwater or drains) passing beneath roads, railways or embankments.

Shay Murtagh Precast is one of the largest producers of precast concrete box culverts in the UK and Ireland. With our modern and mechanised box culvert production facilities, we can produce over 60 metres of culvert section per day.  We manufacture a range of standard stock size box culverts but most units we design and manufacture to meet individual project specifications.  This allows us complete flexibility and enables us to manufacture culverts that can accommodate any situation.


Shay Murtagh Precast culverts are supplied with rebated joints to prevent a vertical drop at the interface between adjacent precast units while simultaneously allowing potential differential settlement to occur between units without introducing unwanted load effects in the culverts. Shay Murtagh Precast has developed a joint detail that is effectively sealed.

Culverts | Precast Concrete Box Culverts - Shay Murtagh Precast | Shay Murtagh Precast

Wingwalls & Headwalls & Mammal Ledges

Shay Murtagh Precast also manufactures, as standard, the precast wingwalls and headwalls used at the ends of the culvert run that ensure effective flow into and out of the culvert and retain the embankments associated with the same.

Wingwalls are effectively precast concrete retaining walls placed at the culvert entrance and exit. The tops of the walls are sloped to match the embankment contours. Wing walls help to form and protect the ends of the culvert and are designed and manufactured to satisfy the required site conditions, loading requirements and ground conditions.

Headwalls, also known as head beams, are typically located between wing walls at the ends of the culvert and are attached to the top slab of the culvert. Headwalls serve to retain any soil above the culvert at the very end of the culvert run in order to form and protect the culvert entrance and exit. Headwalls often also serve as a more suitable attachment for safety fencing and handrails.

Shay Murtagh Precast can include mammal ledges where required within the manufacturing process for culverts. The flexibility in our design and manufacturing process allows us to comfortably accommodate almost any additional concrete components or required provision of openings within the standard culvert section.

Design Service

Our in-house team of highly experienced engineers and technicians deliver a top-quality design and detailing service that is both thorough and flexible. Detailed designs are carried out in-house for each individual project. This allows us optimal flexibility with regards to job-specific constraints and conditions while enabling us to optimize the detailed design and produce the corresponding drawings and details rapidly.

Shay Murtagh Precast Concrete Box Culverts are typically designed and detailed in full compliance with

  • EN 1992-1-1,
  • EN 1992-2,
  • EN 1991-1-1,
  • EN 1991-2,
  • EN 1990
  • EN 1997-1
  • the relevant National Annexes for the said Eurocodes,
  • PD 6694-1,
  • BS 8500-1 and
  • BS 14844:2006+A1:2008.

Where required, we can design and detail culverts to the old British Standard in force prior to the adaption of the Eurocodes. In fact, the range of experience, technical capability and flexibility of our design team enables Shay Murtagh Precast to comply with any required standard or specification.

Variations on Precast Box Culverts

Shay Murtagh frequently manufactures several other types of precast culverts beyond the common box culvert cross section. Large box culverts that cannot be transported as a single unit are constructed from two U-sections for on-site assembly with a ball and socket joint used between the two halves of the finished box section. These are referred to as UAN culverts.

We also supply three-sided U-sections if the project specifies access from above. The U-section can be left permanently open or supplied with a separate precast lid placed on top of the walls of the U-section. Similarly, we design and manufacture three-sided portal frames in situations where a bottom slab is prohibited or deemed to be an economic disadvantage. These include both single unit portal frames for shallower crossings and portal frames placed on precast base legs (referred to as jointed portal frames) for culverts spanning over railway or other crossings with high clearance requirements.

Shay Murtagh also has the capability to design and manufacture double cell box culverts.

We can manufacture skewed and splayed culvert units where required.

Finally, we have developed standard details including closing walls that allow our culverts to be used as attenuation tanks.

Technical Manual for Box Culverts

Please refer to the Shay Murtagh Precast Technical Manual for Box Culverts for further details and sizing guidance regarding our precast box culverts, variations on precast box culverts, and details and additional components associated with precast culverts.

The manual is intended to illustrate the variety of applications and significant benefits of using precast concrete box culverts and provides an overview of their structural design and detailing. The manual includes section thickness tables for a wide range of culvert sizes that will greatly assist with the preliminary design, detailing and costing of culverts. The manual identifies and provides details for the available structural variations of precast concrete box culverts that are manufactured by Shay Murtagh Precast.

The manual presents additional structural components and details that may be used in conjunction with culverts. We believe that this manual combined with our expert technical team will be an invaluable asset enabling you to successfully choose the best and most economical solution to meet your projects requirements.

Get your copy now

To access Edition 1 of the Box Culvert Technical Manual please fill in the form and you will be taken to the download page.

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