Notre Dame Cathedral Restoration Concept

A project I have been developing over the last year. I am still working on selling the concept due to my belief that restoring the spire may exceed engineering safety standards. Also, there are more beautiful options to explore, such as this.

Ancient looking drawings included to help in understanding the design connections between old and new.

All produced with SU and much use of Profile Builder.

ND.rose.period.proposal.177.2.C3 copy|690x397 !


Nicely detailed model, I like the concept.

Stunning work. It’ll take some getting used to Notre Dame without a spire. Wonder, too, how worshipers will react to having an oculus at the crossing. Would it draw attention from the altar?

For me, the restoration design boils down to proportions versus profile. The cathedrals proportions with a spire (even the previous one at about 300’) are quite unbalanced but the profile has an interesting quality to it.
With the dome, the proportions are about as close to balanced as I could get, but it may seem a little heavy in profile. It’s about working with the existing structure to achieve the best balance.

I am sure there would be lots of getting used to a new interior (including new light weight vaulted ceilings) possible new marble flooring, lighting, etc. Just like any new redecorating job, the enjoyment of the new should far outweigh any negative issues.

I like your images but I think that you are introducing a new very heavy and dominant element at a place where there previously was only an accent.

I think that when restoring old buildings as important as this one, you can only introduce new elements when there is a compelling functional or technical reason for doing so.

The spire was a decorative feature added by Viollet-le-Duc. I think that concerning it only two options are available: rebuild it or leave it out entirely.

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Thanks Anssi, critical points.

My website details the multi discipline design approach I have taken. As the structural integrity of the cathedral is not fully understood yet, this concept could be added as a plan B (basic risk management).

CATHEDRAL HISTORY (change log!) - Wikipedia

  • construction of Notre-Dame began between 24 March and 25 April 1163
  • Four phases of construction took place under bishops Maurice de Sully and Eudes de Sully
  • The decision was made to add a transepts at the choir, where the altar was located, in order to bring more light into the center of the church
  • Another significant change came in the mid-13th century, when the transepts were remodeled in the latest Rayonnant style; in the late 1240s Jean de Chelles added a gabled portal to the north transept topped off by a spectacular rose window. Shortly afterward (from 1258) Pierre de Montreuil executed a similar scheme on the southern transept


  • Iconic French architecture and a national treasure
  • Consideration of the cathedrals global interest and attendance
  • Rose window design theme, emphasizing the cathedrals best features
  • A recognizable 21st century restoration
  • Themed concept for improved design consistency
  • Dome design, letting much needed light into the interior
  • Redevelopment, placing a high priority on the function and enjoyment of the cathedral


  • Build on the progressive vision of President Macron (he was voted in on that platform)
  • Strategic planning for long term financial viability
  • Dome design to help stabilize lateral loading
  • Comprehensive museum/plaza design
  • Enhanced building proportions
  • Interior restoration to improve usability

*I like your images, but I think that you are introducing a new very heavy and dominant element at a place where there previously was only an accent.

  • Definitely adding a heavy, significant element, making it more difficult to accept
  • The weight transfers directly down onto four very large supporting columns
  • Being still a concept, there is much that can be altered to give the dome a lighter appearance

I think that when restoring old buildings as important as this one, you can only introduce new elements when there is a compelling functional or technical reason for doing so.

  • A new spire may cause the collapse of the whole building
  • Dome design to help stabilize lateral loading
  • As a design strategist, I place a little higher value on the overall current design of the building, rather than a particular point in history
  • Still a functioning cathedral with 10 million visitors per year
  • There has been a slightly depressing character to the cathedral fighting an uphill maintenance battle which I would like to avoid with a more decorative restoration
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An update, indicating more design development.

As the dome design is quite different and not easy to accept, it helps to integrate the dome into the roof design by emphasizing the upper and lower roof lines.
The dome was initially a hemispherical projection of the largest south rose window, but has been modified to also reflect other cathedral design elements.

Further development of the rose theme along the lower edge of the roof. This space also conceals a new floor which is quite deep and rigid, along with the roof forming a type of torsion box to further stabilize the top of the cathedral walls.


Somehow, to me, it looks like an Indian temple/pagoda…

Well…why not design the original spire, except freestanding on its own architectural steel supports with foundations as micropile supports. Once this design can be shown to be safe and feasible, then integrate it into the restoration. Obscuring or hiding those steel supports would make the Cathedral slightly different, but it would have its original looking spire, except its a safe design. pg

St Peter’s Basilica Dome (~1500-1600) - has some similarities to my dome design, although the intricate detail in mine adds another dimension which may cause it to depart from an ancient gothic impression.


Would be interested to see a close-up image of your dome - especially from underneath. Hard to see all the detail you allude to in the full-cathedral images.

The vision and goals of my multi discipline design concept are to improve the proportions of the building as a fundamental, amongst many other practicalities. (we could obviously argue as to whether a restoration should include these significant changes, but that is the priorities I have set which I believe will result in the most positive long-term outcome).

Although a spire does have aesthetic qualities, especially from the north and south views, it does not balance the overwhelming bulk of the bell towers (bear in mind, past tower additions to Notre Dame would not have had the engineering expertise to explore options available today). Adding some kind of dome is still a compromise as it cannot fully rectify the balance in proportions without becoming very large and unsightly.

The solution then comes through a process indicated in the image. Realigning the towers as the high point, with deliberate height progression from the ambulatory to the towers.

South facing primary rose window.

The rose dome, a hemispherical projection of the window.

The dome cap has had some of the least design development and may benefit from changes.

Dome interior


Thanks! Very impressive work.

Further followup to @Anssi regarding the heavy element appearance of the dome.

After further analysis, the relationship of the dome scale with the transcept is almost as important as with the whole building. So I scaled the dome down a bit more (which would likely happen anyway during design finalization). The challenge with scaling the dome down is to still allow acceptable public access.

The base of the dome has a more clearly defined diamond shape with the points orientated N, S, E, and west which further improve compatibility with the triangular peak of the transcept gables.

Further development on public and private access to and through roof areas. The optional elevators allow public closeup views of the large rose windows and a new private circular hallway has been added beneath the gallery to allow easy private access from the west to east roof areas - possibly conference or office facilities).

Potential public access Rose window interior view.


Still an ongoing speculative project.
More sophisticated dome design.



Developing my VRAY rendering skills…

VRAY handles the model size quite efficiently which is encouraging.