Question 1

Why does Minimal Frame Projects exist?

Accepted Answer

To put the smallest possible amount of aluminium between you and the view, and to do it properly. We are a specialist rather than a general glazing company: our entire business is ultra-minimal sliding doors, which is why we take a project from first sketch through engineering, supply and installation instead of handing a frame to somebody else to fit.

Question 2

You only offer four system families — why?

Accepted Answer

Because we only offer systems we can stand behind and install with our own teams. MFP18 is the slimmest frame on the market at 18 mm, MFP 20/25 covers perimeter-concealed minimalism, Solarlux brings German engineering and passive-house-grade thermal performance, and Vitrocsa is Swiss minimalism for the largest openings architecture allows. If a different system genuinely suits your opening better, we will tell you.

Question 3

Where are your systems actually made?

Accepted Answer

Across the UK and Europe, in the factories that engineer each family. MFP18 is precision minimal sliding, MFP 20/25 is Spanish engineering, Solarlux is German and Vitrocsa is Swiss, with bespoke manufacturing for project-specific elements. Every system is supplied with the manufacturer's published performance figures, and that is what we quote against.

Question 4

Who installs the doors?

Accepted Answer

Our own installation teams, trained and qualified on every system we sell, including Swiss-trained installers for Vitrocsa. We are not a supply-only business that leaves you to find a fitter: the team that fits your doors is the team that answers the phone afterwards.

Question 5

What happens inside the factory?

Accepted Answer

Profiles are extruded and cut to tight tolerance, thermally broken, assembled and glazed to the specification on the drawings, then tested against the published classes for air permeability, water tightness and wind resistance before they ship. Nothing is a stock size — every door is made for your opening.

Question 6

What does a day on site actually look like?

Accepted Answer

Protection first, then setting out and checking the opening against the survey. The track or sub-frame is set and levelled, the panels are lifted and glazed, and the hardware is commissioned and adjusted until it runs silently and seals correctly. We finish with a snag walk-through with you before we leave.

Question 7

Can I see finished projects before committing?

Accepted Answer

Yes. Our South London showroom lets you experience the real sightlines and sliding action in person, and we can send details of recent projects with the system and sizes used on each one. Seeing an 18 mm frame beside a 34 mm frame is worth more than any brochure.

Question 8

How did Minimal Frame Projects start?

Accepted Answer

With one stubborn idea — that the frame should be the smallest part of the door, not the thing you notice first. The business was built as a specialist rather than a general glazing company: instead of selling whatever happened to be on a price list, it was founded around the handful of systems with the smallest sightlines available, fitted by teams we train and control ourselves. That focus is what led to official UK partner status for MFP18 and certified partner status for Vitrocsa.

Question 9

Where is the business now?

Accepted Answer

Four system families and twelve systems, from an 18 mm sightline to passive-house thermal performance, carrying panels up to 20 m² and glazing to 6 m tall. We manufacture across the UK and Europe, engineer bespoke elements for individual projects, and install nationwide with our own MFP-trained teams, working from our South London showroom on domestic and commercial projects alike.

Question 10

Will you tell me if a system isn't right for my opening?

Accepted Answer

Yes, and it is one of the more useful things we do. Every system has published limits — maximum panel area, panel weight, height and performance classes — and if your opening sits outside them, or a different frame would serve you better, we will say so before you spend anything. A minimal frame specified wrongly is an expensive mistake for everyone involved.

Question 11

What exactly is a sightline?

Accepted Answer

The sightline is the visible aluminium standing between you and the view — measured in millimetres at the frame and at the joint between panels. It is the one number that decides how a room feels. An 18 mm frame (MFP18, Vitrocsa 3001) all but disappears, 20 to 25 mm (MFP 20/25) is still extremely minimal, and 34 mm (Solarlux cero III) trades a little more visible metal for passive-house thermal performance.

Question 12

Which is the slimmest system you offer?

Accepted Answer

18 mm, on MFP18-H30, MFP18-H40, MFP18-H50 and Vitrocsa 3001. On MFP18 the surround reduces to just 8 mm once the frame is embedded in the wall, so the opening reads as glass alone.

Question 13

How large can a single glass panel be?

Accepted Answer

Up to 20 m² on Vitrocsa V56, 18 m² on MFP18-H40 and MFP18-H50, 16 m² on MFP 25 and 15 m² on Solarlux cero III, with MFP 25 panels of 4 × 4 m and Vitrocsa V56 panels under 20 m². Sizes most sliding systems simply cannot reach.

Question 14

How tall can the glazing go?

Accepted Answer

Up to 6 m on MFP18-H40 and MFP18-H50, with individual panel weights to 1,000 kg. MFP 25 carries 4,000 mm panels, MFP 20 sashes to 3,000 mm, and Solarlux Highline S frames to 2,800 mm.

Question 15

What is the difference between a lift-and-slide and a standard sliding door?

Accepted Answer

A lift-and-slide door lifts onto its seals as it closes and drops back down as it opens, so it compresses the gasket and carries much heavier glass — Solarlux Highline S handles panels up to 400 kg and 2,800 mm tall. A standard sliding door runs continuously on rollers with brush seals, which is how the largest panels are moved.

Question 16

Can I have a corner that opens with no post?

Accepted Answer

Yes. MFP 20 and MFP 25 both offer a 90° open corner without a fixed mullion, MFP 25 also offers frameless bonded corners, MFP18 has a pillarless corner module, and Vitrocsa systems support corner openings. It is one of the most requested details.

Question 17

Can the doors slide into the wall?

Accepted Answer

Yes. Pocket modules are available on MFP18, MFP 20/25 and Vitrocsa systems, so the panels disappear entirely when open and leave a clean, uninterrupted elevation.

Question 18

Can sliding doors be motorised?

Accepted Answer

Yes. MFP18 offers optional HYMOTOR motorisation with smart controls and motorised open/close, MFP18-H50 can add internal blackout blinds and shutters, and Vitrocsa systems offer motorisation, which we recommend for panels over 500 kg.

Question 19

What glazing can I have?

Accepted Answer

MFP18 takes 28 mm or 38 mm double glazing and 48 mm triple; MFP 20 takes 26 to 30 mm; MFP 25 up to 56 mm; Solarlux cero III is triple glazed; Highline S takes 22 to 60 mm with 50 mm heat-absorbing triple as standard; Vitrocsa V56 takes 56 mm, TH+ 32 to 44 mm and 3001 12 to 26 mm. Specific make-ups such as coatings, laminates and low-iron glass are agreed with your quotation.

Question 20

What finishes are available?

Accepted Answer

MFP 25 is offered in more than 450 finishes including over 150 RAL colours, and Solarlux systems are available to RAL or NCS with around 30 standard shades. Anodised and two-tone finishes are available across the range.

Question 21

Do you do heritage-style frames?

Accepted Answer

Yes — MFP 25 includes a heritage-style configuration, and minimal profiles suit sensitive openings well. We work in conservation areas and on listed buildings where the opening genuinely suits a minimal system.

Question 22

What actually drives the price?

Accepted Answer

The system and its sightline, panel size and weight, the glazing build, the threshold and drainage detail, motorisation, the finish, and the access needed to get the glass in. Structural work, cranes and bespoke detailing add to that. We quote against your actual opening and specification rather than a per-metre figure, because a 6 m panel and a 3 m panel are not the same job.

Question 23

What if I don't know which system I need?

Accepted Answer

Use the system finder. Four questions and we show only the systems that genuinely meet your requirements, with the published figure behind each one. Anything that cannot do what you have asked for is not offered, and our team confirms the specification before quoting.

Question 24

What is the difference between Ug and Uw?

Accepted Answer

Ug is the thermal transmittance of the glass unit itself; Uw is the whole door or window including the frame, so it is always the higher — and more useful — number. A U-value is measured in W/m²K, where a lower figure is better.

Question 25

How thermally efficient are the systems?

Accepted Answer

MFP18-H50 achieves Uw 1.05 W/m²K with Ug 0.5, MFP18-H30 and H40 achieve Uw 1.3, MFP 25 is 1.2 and MFP 20 is Uw ≥ 1.3. Solarlux Highline S achieves Uw from 0.9 with Ug 0.6, Ecoline S Uw ≥ 1.4 with Ug 1.1, and Solarlux cero III is passive-house certified at Uw ≤ 0.80 W/m²K.

Question 26

Do I need triple glazing?

Accepted Answer

Not always. MFP18-H30 and H40 reach Uw 1.3 on 28 mm and 38 mm double glazing, which is excellent for most UK homes. Triple glazing takes MFP18-H50 to 1.05 and vitally improves acoustics. For exposed, coastal or cold sites, and for any passive-house target, triple is the right call.

Question 27

Is passive house certification relevant to me?

Accepted Answer

If you are building or renovating to a very low energy standard, yes — Solarlux cero III is certified at Uw ≤ 0.80 W/m²K with a 72 mm panel depth. If you are not pursuing certification, MFP18-H50 or Solarlux Highline S give you most of the performance with a much slimmer frame.

Question 28

How quiet are the doors?

Accepted Answer

Acoustic performance ranges from Rw 36 dB on MFP18-H40 and H50, Rw 37 dB on MFP18-H30 and Rw up to 41 dB on MFP 20, to Rw 44 dB on Solarlux cero III. Triple glazing and laminated make-ups raise these further, and they are the single most effective fix for road or aircraft noise.

Question 29

Aren't minimal frames cold?

Accepted Answer

No. The frame is thin, not thermally compromised: profiles are thermally broken and paired with double or triple glazing, which is how the same 18 mm frame delivers Uw 1.05 W/m²K on MFP18-H50. Solarlux cero III goes further still and is passive-house certified.

Question 30

Can I really have a completely level threshold?

Accepted Answer

Yes. Flush, integrated thresholds with stainless-steel gutters and drainage are available across the MFP18 range, MFP 25 offers a continuous flush threshold with optional ACO drainage, Solarlux systems use level-access tracks with cascading drainage, and Vitrocsa systems are Part M compliant with a flush level-access floor. Barrier-free thresholds are the norm, not the exception.

Question 31

Will they leak in driving rain?

Accepted Answer

Every system is tested and published against water tightness classes: Class 8A on MFP18-H40 and H50 and Solarlux Highline S, Class 7A on MFP18-H30 and MFP 20, and 9A on Solarlux cero III, with wind resistance to Class C5. Integrated gutter and cascading drainage details keep water out of the track and away from the floor.

Question 32

How secure are they?

Accepted Answer

MFP18 uses a multi-point locking system concealed in the frame and is rated RC2. Solarlux cero III carries RC3 burglar resistance, the highest certified level in the range, and Highline S is certified RC2 / RC2N. MFP 25 locks at the central junction with a security flip handle as standard.

Question 33

Will the glass scratch, or the seals fail?

Accepted Answer

Glass is far more durable than most people expect — damage comes from abrasive cleaners, grit left in the track and site debris, all of which are avoidable. Seals and brushes are serviceable components rather than permanent ones; they are inspected and replaced as part of servicing, which is one reason we recommend an annual visit.

Question 34

How much maintenance do the doors need?

Accepted Answer

Very little. Keep the track clear of grit, wipe the frames and glass with mild soapy water and a non-abrasive cloth, and keep the drainage clear. An annual service covers the seals, rollers, hardware adjustment and drainage. Solarlux Highline S even carries an integrated brush that cleans the track with every panel movement.

Question 35

What is a warm-edge spacer, and does it matter?

Accepted Answer

It is the spacer bar between the panes of a sealed unit, and it matters more than most people realise. A standard aluminium spacer conducts heat straight around the edge of the glass, which makes the inner edge colder, raises the risk of condensation and drags the whole U-value down. A warm-edge spacer breaks that thermal bridge — Solarlux Highline S quotes Ug 0.6 W/m²K with a warm edge. If you are specifying triple glazing, insist on it.

Question 36

Which glass should I choose?

Accepted Answer

Start with the build the system is designed around: 28 mm or 38 mm double and 48 mm triple on MFP18, up to 56 mm on MFP 25, and 50 mm heat-absorbing triple as standard on Highline S. Beyond that, low-iron glass removes the green edge tint and makes a slim frame look even slimmer, solar-control coatings reduce heat gain on south-facing glass, self-cleaning coatings cut maintenance on tall or hard-to-reach panels, and laminated make-ups add security and acoustic performance. We agree the exact make-up with your quotation so nothing is left to guesswork.

Question 37

How do thresholds and drainage work?

Accepted Answer

The track is not simply set into the floor and left there. MFP18 uses an integrated stainless-steel gutter with drainage, MFP 25 offers a continuous flush threshold with optional ACO drainage, Solarlux systems use level-access tracks with cascading drainage, and Vitrocsa runs on thermally broken tracks with stainless-steel floor bearings. The drainage route is designed at survey stage, because it decides the floor build-up and where water ends up.

Question 38

What is Part M, and when does it apply?

Accepted Answer

Part M is the part of the Building Regulations that deals with access to and use of buildings, and in practice it is what people mean by level access. Vitrocsa systems are Part M compliant with a flush level-access floor, and flush thresholds with integrated drainage are available across the MFP18 range and on MFP 20/25. Barrier-free thresholds are standard on everything we install, and the detail is confirmed at survey.

Question 39

What happens after I enquire?

Accepted Answer

You hear back within 14 hours. From there: consultation at the showroom or by phone, survey and engineering, design and specification with configuration drawings and U-value calculations, manufacture, installation by our own teams, and aftercare with warranty cover, servicing and glass replacement.

Question 40

What does the survey involve, and what do you need from me?

Accepted Answer

We measure the opening precisely, review the structure and head detail, check the floor level and where the track and drainage will run, and assess access for the panels. Anything you have — plans, elevations, drawings from your architect — helps, but it is not essential. The survey is where the system and glazing build are confirmed.

Question 41

Do you supply only, or supply and install?

Accepted Answer

We do both, but we specialise in full supply and installation with our own trained teams, because that is how the flush thresholds and silent operation these systems are capable of actually get delivered. Some clients use their own installer; we will always say that a system this precise is best fitted by the team trained on it.

Question 42

Can you work with my architect, builder or project manager?

Accepted Answer

Yes, and it usually makes the project smoother. The sequence matters: the opening is formed and the structure checked before we survey, then we set out, install the track or sub-frame, fit and glaze the panels and commission the system. We provide coordination drawings and interface details so the other trades know exactly what they are building to.

Question 43

Who will I deal with through the project?

Accepted Answer

You get a named contact from enquiry to handover and aftercare, rather than being passed between departments. Day to day, our sales team is on 0207 550 6550 and on sales@minimalframeprojects.co.uk.

Question 44

How long will the whole project take?

Accepted Answer

Every door is made to order, so the programme depends on the system, the glazing build and any structural work. We confirm a precise programme with your quotation, and keep you updated through manufacture and installation.

Question 45

Do you handle planning and building regulations?

Accepted Answer

We supply the technical documentation your architect or building control officer needs — U-values, performance classes, Part M level-access details and interface drawings. The application itself stays with you and your advisers, but you will have everything required to support it.

Question 46

Do you work on listed buildings and in conservation areas?

Accepted Answer

Yes, where the opening genuinely suits a minimal system. Slim profiles and heritage-style configurations work well in sensitive buildings, and we can adapt detailing to suit the existing structure. Listed building consent and planning remain with you and your advisers; we provide the drawings and specifications they need.

Question 47

What are your installation standards?

Accepted Answer

Protection goes down before anything else. Setting out is checked against the survey before the track or sub-frame is fixed, tolerances are verified at the head, jamb and threshold, and the panels are glazed and the hardware commissioned once the structure is settled. We work to a commissioning checklist — sliding action, seals, locking, drainage and thresholds — and finish with a snag walk-through and sign-off with you before we leave site.

Question 48

How often will I hear from you?

Accepted Answer

You have a named contact for the project, and you hear from us at the points that matter: after the survey, when the order is confirmed, when manufacture starts, when delivery is booked, and around installation and handover. If something is urgent, the sales line is 0207 550 6550 and the email is sales@minimalframeprojects.co.uk — you will not be passed around to find an answer.

Question 49

What about party walls?

Accepted Answer

Party wall matters sit between you and your neighbour, and they are handled by your own party wall surveyor rather than by us. Where an opening or a fixing sits in or against a shared wall, we provide the drawings, fixing details and structural information your surveyor and engineer need, and we build to whatever detail comes out of that process.

Question 50

Do you provide drawings and technical information?

Accepted Answer

Yes — PDF and DWG details, U-value calculations, specification clauses and product datasheets, on request. Every figure we quote comes from the manufacturer's published data rather than a marketing summary.

Question 51

Can you help me write a specification?

Accepted Answer

Yes. The specification generator on this site builds an NBS-style clause from manufacturer-published data, which you can print or hand to your project team, and our team will review a specification you have already written and flag anything that does not stack up.

Question 52

Do you offer CPD or support for architects and specifiers?

Accepted Answer

Yes. We offer CPD sessions on minimal sliding systems — sightlines, thermal performance, thresholds and structural interfaces — plus specification and detailing support for individual projects. Get in touch to arrange one.

Question 53

Do you work on commercial projects and tender?

Accepted Answer

Yes. We work on both domestic and commercial projects, and we can supply method statements, risk assessments, insurance documentation, references and a construction programme with your tender submission. Our teams work to CDM 2015 requirements on commercial sites and are used to operating alongside a principal contractor and following site-specific rules.

Question 54

Where do you cover?

Accepted Answer

Our showroom is in Surbiton, Surrey, and London, Surrey and the Home Counties are our core area. We install nationwide, including projects where a particular system or a specific installation team is required.

Question 55

How do you get a six-metre panel to site?

Accepted Answer

With planning rather than hope. Panels are made to order, crated for transport, and the delivery is timed to suit the build programme, with lifting equipment, machine access or a crane arranged in advance where the access demands it. Panels are checked on arrival before anything is lifted.

Question 56

Where can I see recent projects and new system launches?

Accepted Answer

Ask us and we will send you details of recent installations, including the system, sizes and specification used on each one. New systems and product updates reach our showroom as soon as they are released, and the full current range with its published figures is on the systems pages of this site.

Question 57

What warranty comes with the doors?

Accepted Answer

Our aftercare covers warranty, servicing and glass replacement for the life of the doors, and each system carries its manufacturer's warranty alongside our workmanship cover. The exact periods and what is included are set out in our Terms & Conditions of Sale and in your warranty documentation, which we are happy to send before you order.

Question 58

What if something goes wrong after installation?

Accepted Answer

Call or email us and we will deal with it. Servicing, seal and roller replacement and glass replacement are all part of what we do, and anything that cannot be resolved directly is handled under our complaints procedure, which sets out timescales and who to escalate to.

Question 59

How soon will I hear back from you?

Accepted Answer

Within 14 hours of submitting an enquiry. Every specification that comes through is reviewed by our team before we respond.

Question 60

Can I visit the showroom?

Accepted Answer

Yes, and we would recommend it. Call 0207 550 6550 or send an enquiry and we will arrange a time that suits you at our South London showroom, where you can see the systems, the sightlines and the sliding action for yourself.

Question 61

Do you take on installers or apprentices?

Accepted Answer

If you are an experienced installer or starting out and want to work on minimal sliding systems, we would like to hear from you. Send your details through the contact page and we will keep them on file.

Question 62

How do I get started?

Accepted Answer

Three ways: request a quote with your approximate dimensions, use the system finder if you are still deciding, or call us on 0207 550 6550. Any of them gets you straight to the team that will survey and install the doors.

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