Building type
Cold at the desks or losing heat through the roof? Office insulation starts with the construction: we apply closed-cell spray foam to ceilings, concrete soffits, metal roof undersides and concrete roof decks, with work planned around your week.
Recent soffit projects
Installation footage and photographs from HOLVEM's own concrete soffit projects: an undercroft void, live retail soffits, a new-build fit-out and an external canopy.
Why spray foam
Four things the office notices, with the work fitted around the working week.
Ceilings, concrete soffits, metal roofs and concrete roof decks insulated, so warmth stays put.
One layer wraps beams, edges and services, with the depth set to the target.
Class 1 to BS 476-7 uncoated. B-s2,d0 when NexSeal LE is coated with DC315.
Ceiling panels out, metal roofs boarded over afterwards, soffits reached from below.
Three short steps: the building and the problem, a postcode, and how to reach you.
01 The problem
Before adding more heating, look at the surfaces around the people using it. A bare roof or concrete ceiling lets heat leave the office; gaps around beams and services add draughts. On cold surfaces, moisture in the air turns into condensation. The construction tells us where the insulation needs to go.
The office · Cold overhead surfaces
What it costs the working day
So what is the solution?
02 · THE SOLUTION03Working around the office
Once we know which surface needs insulating, we can plan access around the working week. An undercroft job is reached from below; ceiling and roof work inside the office needs a released area. We agree the sequence with the people who manage the building.
04Enverge NexSeal LE
Enverge NexSeal LE is a two component closed cell polyurethane, spray applied directly onto the prepared substrate. As it cures, it expands and sets into one rigid, continuous layer, bonding into corrugations, laps, fixings and awkward junctions without being cut, jointed or mechanically fixed. In an office that is the beam, the column head and the edge, wrapped in one layer with no joint to open.
That matters because most insulation problems start at the gaps.
Board systems can leave voids at ribs, laps and junctions, and every gap is a potential cold bridge where warm internal air meets a cold surface and condensation forms, hidden behind the insulation. NexSeal LE is applied as one continuous bonded layer, so there is nowhere for that to start: a sealed, stable building envelope that controls condensation, reduces heat loss and protects the structure underneath.
HOLVEM also installs open-cell foam. It is a different product with its own data sheet, specified for different objectives; it is not what goes onto a cold roof underside or a concrete soffit. Open-cell system data · Closed-cell system data
05The objective sets the depth
What does the office need? Pick one below and you will see the depth that does it, and what it won’t do. The beams and edges go into the calculation, and the survey confirms the figure.
75 mm and aboveReach a calculated U-valueA figure for the building to meet, calculated with the beams and edges in it.
25 mmControl condensationKeep the surface above the dew point of the air that meets it.
The surface stops being the coldest one the air meets, so nothing forms on it and nothing drips off it. In an office this is rarely the whole objective; it usually comes with the next one.
50 mmRetain heatHold the heat in the office, so there is less to bring back in the morning.
Controls condensation on the surface and cuts the conductive loss through it, so the office holds its heat. Confirmed before we spray against the building's use and heating.
75 mm and aboveReach a calculated U-valueA figure for the building to meet, calculated with the beams and edges in it.
The usual objective in an office: a figure for the building to meet, calculated for this build-up with the beams and edges in it. A contract-specified 0.18 W/m²K has needed 135 to 140 mm on a concrete deck and on live retail soffits.
Depth to suit + DC315 coatingAchieve Euroclass BA reaction-to-fire classification: B-s2,d0 on the coated system.
Where the specification requires a reaction-to-fire classification, the DC315 intumescent coating is applied to the cured layer. The foam depth under it depends on the scope and what the building has to achieve. B-s2,d0 to BS EN 13501-1 belongs to the coated NexSeal LE and DC315 system as tested: 35 to 40 mm of NexSeal LE on 9 mm plasterboard with DC315 at 0.7 mm wet film thickness (BTTG report 27/06638/12/24), confirmed for each project against the fire strategy. Uncoated, the layer carries Class 1 surface spread of flame to BS 476-7, which is not a Euroclass.
Four depths, drawn to one scale and measured from the surface. The objective and the calculation set the thickness on your building.
Know the objective? Start a project brief for your building.Three short steps: the building and the problem, a postcode, and how to reach you.
Start a project brief
Not sure which depth you need?
Thickness and objective
Four depths, what each one does, and what it does not claim.
Read thickness and objective 06Checks and handover
Before the work, we check the construction, moisture conditions and access, then agree any lining or coating requirements. The depth is confirmed before we spray. We use certified spray foam systems, which we apply as an accredited installer for the manufacturer. Depth and coverage are recorded in your QA evidence pack, so the office file holds more than a promise.
What you get after the survey
Five things in writing, whether or not you go ahead.
A firm figure starts with the building. Yours takes a minute to describe.Building, ceiling or roof, what you are seeing, and how to reach you. A real figure for your building the same working day; nothing sent to anyone else.
Get my estimateProject records
With over 20 years' experience, we have worked on projects with very different specifications and needs. Here are some recent ones, and what the outcome was.
Project recordConcrete soffit work at The Box, PlymouthThe Box is a civic museum, gallery and archive. Its published record covers 787 m² of concrete soffit insulated with 120 mm of closed-cell foam to a specified U-value of 0.18 W/m²K. Adhesion and thickness were checked before site inspection. The U-value is a calculated thermal target. That is evidence of soffit work; your office needs its own calculation.Read The Box project record. 
Project recordPondswick substation, Luton127 m² of concrete soffit insulated and coated with DC315 under live switchgear.Read the record 
Project recordA new-build warehouse deck, Ipswich300 m² of concrete slab on steel decking, insulated from below with 135 mm of closed-cell in four days.Read the record 07Straight answers
The questions facilities managers, landlords and engineers actually ask on the call, answered the way the specialist answers them. A question we have not answered? Ask it on the call. No obligation.
The next step
If you already know the thickness or U-value you need, we price to it and confirm it is right; if not, we work it out with you. The estimator at the top takes about a minute and asks for nothing until the reading is on screen. "Not sure" is a useful starting point.
Prefer to talk? Call 01932 506658 Enquiries received before 3pm on a working day are contacted the same day; after 3pm, the next working day.