RB-A
Ballast frame – no roof penetrations
Nothing is drilled into the roof. Suitable for concrete slabs with warm-roof or inverted-roof construction.
Diagram labels in Swedish
The whole energy system · Wind power
Rooftop wind power – when it is right, and how we know
RoofBase is Solpulsen’s standardised mounting system for small vertical wind turbines on apartment buildings, offices and industrial buildings.
Rooftop locations often have lower average wind speeds and more turbulence than expected – British measurements of small rooftop turbines (Warwick Wind Trials, 2009) found that they generally produced far less than expected.
That is why we measure for six months before recommending turbines, and we never promise production without measurement data.
For your board
Before your board can decide on rooftop wind power, you need three things: to know whether your roof can support it, to know whether there is enough wind, and to know who is responsible for what. This page addresses those questions. We always start with a roof assessment and six months of wind measurement – only then do you receive information that the board can use to make a decision. No turbine is purchased until the roof and the wind have been checked.
Measure first. Decide afterwards.
How we plan before anything is ordered
Background information
Structural drawings, the construction of the roof or wall, and photographs. We make an initial assessment of the roof type and likely variant – or whether the wall is the right location.
Measure first
Six months of rooftop wind measurement using an ultrasonic anemometer on a mast and a data logger, with a report adjusted against long-term data. Below approximately 5 m/s at hub height, we advise against turbines; 5 to 6 m/s is possible and the board decides based on measured production; above 6 m/s, we recommend proceeding.
Investigation openings
An investigation opening at each tower location reveals the layers, slab thickness, concrete class and reinforcement position. The opening determines whether RB-B1 or RB-B2 is appropriate. On a wall, it is replaced by test drilling and pull-out testing of anchors in the load-bearing concrete.
Structural engineer
A qualified structural engineer checks the loads, base, anchors or ballast, and the load-bearing capacity of the roof or wall against the site conditions, and prepares stamped documents.
The municipality
We consult the municipality for every project before anything is ordered. Notification to the electricity distribution company.
Loads transferred to the supporting structure
The mounting system that makes it possible – Solpulsen RoofBase
RB-B1
Column – one tube down into the concrete
A single steel tube runs from a base plate on the concrete slab, through the roof construction, up to the turbine.
Diagram labels in Swedish
RB-B2
Four-legged frame – low forces
The large lever arm results in low forces at each mounting point, and the four penetrations are standard pipe penetrations for the roofing contractor.
Diagram labels in Swedish
RB-D
Steel structure – anchored to the roof purlins
The RB-A frame on load-distribution plates, anchored to roof purlins or primary beams with through-bolts and backing plates.
Diagram labels in Swedish
RB-WConcept
Wall bracket – a wall instead of the roof
Only on load-bearing concrete or steel walls with no residential rooms behind them.
Diagram labels in Swedish
Loads are transferred to the building’s supporting structure – the concrete slab or steel frame – rather than the waterproofing. Sealing by an authorised roofing contractor, the roof warranty is retained, and a structural engineer stamps each installation.
The whole energy system
How it connects to the rest
Electricity from the turbine enters the building’s electrical system in the same way as solar electricity.
Where battery storage and smart control are present, wind is used when it is available – often in the evening, at night and during the winter half of the year, when solar production is low.
Wind, electricity and heat measurements are arranged so that the board can see everything in the same report.
Where we say no
- Timber roofs on trusses cannot support it; there we propose a ground-mounted mast.
- We do not anchor into lightweight concrete elements; these require load distribution across supporting lines or anchoring into steel beams below. We never attach to timber.
- We do not mount RB-W on walls with residential rooms directly behind or below them – a turbine attached to a wall transfers structure-borne noise and vibration into the building.
Three questions before your decision
Does it damage the roof?
No, if it is done correctly. RB-A does not require any holes.
How much electricity does it produce?
It depends entirely on the wind on your particular roof. That is why we measure for six months before recommending turbines, and we never promise production without measurement data.
Is planning permission needed?
A wind turbine requires planning permission if it is more than 20 metres above ground level or stands closer to the property boundary than its height. Mounting a wind turbine on a building is no longer a separate criterion for requiring planning permission, but permission may be needed as a change to the building’s exterior – for example, within a detailed development plan where the roof faces a public place, or on a building of particular heritage value. We consult the municipality for every project before anything is ordered.
Measure first. Decide afterwards.
Your next step
No turbine is purchased until the building and wind conditions have been checked.
Book an introductory meeting
45 minutes · free of charge
Read the full RoofBase guide on our wind site (in Swedish)