Mounting configurators compared

Solispec vs mounting configurators (K2 Base, fischer, Renusol, Schletter)

K2, fischer, Renusol and Schletter give installers free planning tools for their own mounting systems. Solispec is an independent browser tool for the frame itself. This page puts them side by side and says where each one is the better choice.

Design your first plant for free Pricing

In the browser, nothing to install, no card: the Start plan is free.

Ground frame designer

Design the ground frame for your solar plant

Solispec picks the profiles and posts, checks the frame against snow and wind to the DBN and prices it down to the last bolt.

Design the frame Calculate for free

Two kinds of tool that get compared by mistake

A maker’s configurator answers one question: which parts of our system does this roof need, and does the system hold under the local snow and wind? It is free because it sells the maker’s rails, hooks and ballast trays. It also carries the maker’s statics approvals, which matters when the building authority or the roof owner asks for a proof.

Solispec answers a different question: how should a frame be built from the profiles and panels you have chosen, and does it pass? It covers ground-mounted tables, flat roofs and pitched roofs, and it continues past the structure into the bill of materials, drawings, a PDF report and a client proposal. It does not carry any maker’s approval.

Feature matrix

Competitor cells are only what each maker’s public page states. Where a page is silent the cell says so, because silence is not a no.

	Solispec	K2 Base	fischer SOLARPANEL-FIX	Renusol PV-Configurator	Schletter Creator
Ground mount	Yes	Not stated on the vendor’s site	Not stated on the vendor’s site	Not stated on the vendor’s site	Not stated on the vendor’s site
Flat roof	Yes	Yes	Yes	Not stated on the vendor’s site	Yes
Pitched roof	Yes	Yes	Yes	Not stated on the vendor’s site	Yes
Not tied to one maker’s system	PartlyAny panel by its size; profiles and rails from the Solispec catalogue.	NoThe tool plans “your K2 mounting system”.	Not stated on the vendor’s site	Not stated on the vendor’s site	Not stated on the vendor’s site
Snow and wind from the address	YesAddress search. Ukraine by region; Poland, Germany, Spain by the nearest main city.	Yes	Yes	Yes	Yes
Which countries’ standards	Ukraine (DBN V.1.2-2). Poland, Germany, Spain: the national annex zones at the nearest main city, offered as a guide. Elsewhere you enter s_k and q_b.	Loads are “determined automatically”; the standard is not stated on the page.	Eurocode 1 (EN 1991) from the site’s geolocation; countries not stated.	Snow and wind standards of 17 countries; a Eurocode safety concept.	Regional loads by postcode or town from a worldwide database; the standard is not stated.
Structural checks shown	Yes	Yes	YesEN 1993 and EN 1999 checks plus fischer specifications.	Yes	Yes
Bill of materials	Yes	Yes	Yes	Yes	Yes
Drawings or assembly plan	Yes	Yes	Yes	Yes	YesPlans export as DXF (Configurator).
PDF report	Yes	Yes	Yes	Yes	Not stated on the vendor’s site
Client proposal	Yes	Not stated on the vendor’s site	Not stated on the vendor’s site	Not stated on the vendor’s site	Not stated on the vendor’s site
In the browser	Yes	Yes	Yes	Yes	PartlyCreator runs in the browser; the older Configurator is a Windows program.
Free to use	PartlyStart plan: checks and basic drawings. Proposal and all drawings from Pro.	FreeThe tool is free; the mounting system it plans is K2’s.	Not stated on the vendor’s site	Free	Free
Price model	Start is free; Pro and Business monthly, prices on the pricing page.	Free of charge, says the maker’s page.	Not stated on the pages checked.	Free, says the maker’s page.	Creator is free; the Windows Configurator is free for trade companies, with a login.

Checked November 2, 2026

Where the makers’ tools are better

Be fair to them. For a roof built with one maker’s system, the maker’s own tool is often the right first stop:

It costs nothing and needs no licence, and for a roof system from that maker it is the shortest path from layout to parts list.
The result is tied to a certified system. Where a building authority wants a statics proof for a product, only the maker can stand behind it.
It knows its own components: hook types, clamp ranges, tray weights, the maker’s tested wind-tunnel data. A general tool treats these as profiles and bolts.
Warranty and ordering are connected. Some makers extend a warranty to projects designed in their tool, and several link to their webshop or to inverter planning software.

Where Solispec fits

Solispec is the better fit when no maker’s system decides the job: a ground-mounted table on piles, a frame you fabricate from steel C profiles, a flat roof with ballast you size yourself, or a quote that compares several suppliers. The same project then carries through to drawings, a cutting list, a PDF report and a proposal the client opens from a link.

It is also the place to run a quick check before you pick a system. The loads come from the address, the structure is checked against them, and you see which member or fixing governs. The rules it follows, and what it leaves out, are on the methodology page.

How to choose

If the roof is a standard roof and you already buy from K2, fischer, Renusol or Schletter, plan it in their tool and keep the statics report they issue. If the frame is yours, the site is a field, or you need the client proposal and the estimate from the same data, use Solispec. Many installers use both.

One caution applies to every tool on this page, ours included: the result is preliminary until a qualified engineer has checked it for the actual site and the actual building.

Where to go next

Questions

Is Solispec a replacement for K2 Base or fischer SOLARPANEL-FIX?

Not for a roof that is built with that maker’s system and needs its approval. It is an alternative when the frame is not one maker’s product, or when you want drawings, an estimate and a proposal from the same project.

Does Solispec work for ground-mounted systems?

Yes. Ground tables on piles or ballast, flat roofs and pitched roofs are all modes of the designer. The configurators on this page state roof types only; none of them says it covers ground mounting.

Which countries’ snow and wind rules does Solispec use?

Ukraine by DBN V.1.2-2. For Poland, Germany and Spain it offers the national annex values of the nearest main city as a guide, and the engine combines them by EN 1990 with the snow and wind rules of EN 1991-1-3 and -1-4. For other countries you enter the characteristic snow and wind values yourself.

Is there a free plan?

Yes. The free calculators need no account, and the Start plan of the designer is free with the structural checks on. The proposal, every drawing and a PDF without the watermark need a paid plan; see the pricing page.

Can I rely on the result without an engineer?

No, and the same goes for the makers’ tools. The result is a preliminary calculation. A qualified engineer must check it against the site and the local building rules before anything is built.

Sources

About the competitors only what their public pages state (November 2, 2026); what they do not state is marked «not stated». No competitor prices: they change, see the vendor’s site.