Curious to find out if any smaller firms are utilizing laser scanning for establishing an existing BIM model when working reno projects.
and
If any of those smaller firms are utilizing AR in designs yet.
Feel free to describe equipment, software, workflow, etc. about above mentioned technologies.
SneakyPete
Aug 17, 21 12:40 pm
Workflow:
1. Get a model from the scanning company.
2. Rebuild the model from scratch using model elements that work with your firm's standards. Refer to point cloud for places that are tricky.
gibbost
Aug 17, 21 12:48 pm
We use Lidar scanning for existing buildings. As Pete points out above, we have found that the project team that will ultimately use the model needs to have a vested interest in the scanning and initial model development. We used to have a dedicated group here in the office that did solely this--but we learned pretty quickly that what one person finds important (when capturing existing conditions) might not be what another person thinks.
Never had any experience with using an outside company to scan and build the model. For reasons listed above, I can't see this as a value-add to a project.
SlammingMiruvor
Aug 17, 21 12:52 pm
I haven't used and LIDAR or 3D scanning for renovation work. My gut tells me that it's going to produce a BIM model that's too detailed and be a pain in the ass to work with.
We've used AR for community engagement sessions. I really loved it and felt like we got better engagement from people using the VR, instead of looking at renderings. Kinda skeevy with COVID these days though, not sure how much action you'd get.
natematt
Aug 17, 21 4:30 pm
I almost got a job at a 4 person firm that did a lot of city related work with LIDAR like 8 years ago. Wonder how they are doing.
We occasionally use 3d scans for reno work. It's kind of hit or miss in my opinion, as noted above you kind of have to rebuild everything, and the problem is then you're still relying on your people to do things right and trust the scan. And when it's the client providing the scans, if you want to take issue with things for fix things it becomes a liability problem. Working on existing buildings is always an interesting challenge.
My favorite LIDAR project is from Radiohead.
LEDO
Aug 17, 21 4:57 pm
@natematt That is pretty cool! Thank you for sharing.
joseffischer
Aug 17, 21 4:59 pm
I build all our own models from pointcloud. We recently purchased the camera, forget which kind. Historically we got one local company to give us .rcp files by floor, stairwell, and exterior... properly placed so that if I combine any 2 files they are located correctly. Our comps often couldn't handle entire building files all in one go.
Multivista is a company that 3rd party provides pointclouds at a (inter?)national level. I've never been pleased with their product. I've had the points of the exterior face of boarded up windows (plywood) be inside the building past the points that are supposed to represent the exterior glazing. I've had point clouds of relatively empty core and shells columns not line up floor to floor. Going out to verify results in columns sitting on top of eachother within 1/8" (as expected).
TL:DR, if you're being paid to really do as-builts from scratch, someone like me, trained in doing it oldschool, but willing to learn new things, will definitely be able to get a finished existing conditions model up and running faster doing it with pointcloud, with the added bonus of having the point clouds to look at during DD/CDs.
proto
Aug 19, 21 10:59 am
I have it in my head you have to redraw everything to derive sensible plans from a point cloud as-built. [somewhat parallel lines for walls, corridors & openings, etc]
Is this true? I’d be interested to hear a breakdown of the actual process between the point cloud & drafted lines (or BIM model). Is there an AI-derived plan first from PC data? Then you correct it. Or you use it as an underlay to draft over?
joseffischer
Aug 19, 21 2:34 pm
the floor sized files are not too large to hurt revit performance, so we input those first. wall thicknesses and type are derived from the pointcloud (opened separately in recap) with a mixture of field photos, pointcloud photos, and pointcloud measurements. I'm hardpressed to draw anything off of rectangular but if I can verify a structural element that's truly off, I'll denote it in a detail group of my own field measurements/decisions, showing a dash line of the expected location for a column, as example, before putting in the real column 2" over. I've already visited the site and my first step is to verify the pointcloud-claimed floor levels and grid lines against some of my own measurements. More often than I'd like, something is trapezoidal and if it's a main wall (loadbearing brick?) I'll draw it that way. I've even had existing 1920ish drawings surface that showed walls built to the property line with 89.7 degree or even 89 ??min ??sec measurements. At that point it's pretty hard to ignore the info provided and just draw rectangles.
joseffischer
Aug 19, 21 2:36 pm
also, it's not really redrawing anything as neither step is drawing. the point clouds appear in 3d space just like you'd take a photo, and the revit wall element is a modeled thing you manipulate. If there's really any duplication of work it's that I'm taking field measurements (barely any compared to traditional methods of capturing as-builts) and then I'm taking point cloud measurements... but you know what they say, measure twice, place a wall once
thatsthat
Aug 17, 21 6:05 pm
We have a third-party company that provides LIDAR scans of existing projects for us. We have to be very specific about the goals of the scanning and what we intend to produce from the scans to make sure we get what we need. We do our own CAD/BIM modeling from the scans; old buildings are typically not square and can have some funky-ness due to settling over time, construction/installation errors, weird owner-performed repairs over time, etc. and we prefer to make our own determination on how that is approached when modeled/drafted. Having point clouds has helped us reduce the initial drafting time (draftsmen can get up and running before a site visit is performed) and we end up having a fairly comprehensive record of images showing existing conditions. Typically generally you always miss something when photographing. We also do on-site measurements just to get a double-check of what we are seeing in the point cloud, especially in high detail areas.
Curious to find out if any smaller firms are utilizing laser scanning for establishing an existing BIM model when working reno projects.
and
If any of those smaller firms are utilizing AR in designs yet.
Feel free to describe equipment, software, workflow, etc. about above mentioned technologies.
Workflow:
1. Get a model from the scanning company.
2. Rebuild the model from scratch using model elements that work with your firm's standards. Refer to point cloud for places that are tricky.
We use Lidar scanning for existing buildings. As Pete points out above, we have found that the project team that will ultimately use the model needs to have a vested interest in the scanning and initial model development. We used to have a dedicated group here in the office that did solely this--but we learned pretty quickly that what one person finds important (when capturing existing conditions) might not be what another person thinks.
Never had any experience with using an outside company to scan and build the model. For reasons listed above, I can't see this as a value-add to a project.
I haven't used and LIDAR or 3D scanning for renovation work. My gut tells me that it's going to produce a BIM model that's too detailed and be a pain in the ass to work with.
We've used AR for community engagement sessions. I really loved it and felt like we got better engagement from people using the VR, instead of looking at renderings. Kinda skeevy with COVID these days though, not sure how much action you'd get.
I almost got a job at a 4 person firm that did a lot of city related work with LIDAR like 8 years ago. Wonder how they are doing.
We occasionally use 3d scans for reno work. It's kind of hit or miss in my opinion, as noted above you kind of have to rebuild everything, and the problem is then you're still relying on your people to do things right and trust the scan. And when it's the client providing the scans, if you want to take issue with things for fix things it becomes a liability problem. Working on existing buildings is always an interesting challenge.
My favorite LIDAR project is from Radiohead.
@natematt That is pretty cool! Thank you for sharing.
I build all our own models from pointcloud. We recently purchased the camera, forget which kind. Historically we got one local company to give us .rcp files by floor, stairwell, and exterior... properly placed so that if I combine any 2 files they are located correctly. Our comps often couldn't handle entire building files all in one go.
Multivista is a company that 3rd party provides pointclouds at a (inter?)national level. I've never been pleased with their product. I've had the points of the exterior face of boarded up windows (plywood) be inside the building past the points that are supposed to represent the exterior glazing. I've had point clouds of relatively empty core and shells columns not line up floor to floor. Going out to verify results in columns sitting on top of eachother within 1/8" (as expected).
TL:DR, if you're being paid to really do as-builts from scratch, someone like me, trained in doing it oldschool, but willing to learn new things, will definitely be able to get a finished existing conditions model up and running faster doing it with pointcloud, with the added bonus of having the point clouds to look at during DD/CDs.
I have it in my head you have to redraw everything to derive sensible plans from a point cloud as-built. [somewhat parallel lines for walls, corridors & openings, etc]
Is this true? I’d be interested to hear a breakdown of the actual process between the point cloud & drafted lines (or BIM model). Is there an AI-derived plan first from PC data? Then you correct it. Or you use it as an underlay to draft over?
the floor sized files are not too large to hurt revit performance, so we input those first. wall thicknesses and type are derived from the pointcloud (opened separately in recap) with a mixture of field photos, pointcloud photos, and pointcloud measurements. I'm hardpressed to draw anything off of rectangular but if I can verify a structural element that's truly off, I'll denote it in a detail group of my own field measurements/decisions, showing a dash line of the expected location for a column, as example, before putting in the real column 2" over. I've already visited the site and my first step is to verify the pointcloud-claimed floor levels and grid lines against some of my own measurements. More often than I'd like, something is trapezoidal and if it's a main wall (loadbearing brick?) I'll draw it that way. I've even had existing 1920ish drawings surface that showed walls built to the property line with 89.7 degree or even 89 ??min ??sec measurements. At that point it's pretty hard to ignore the info provided and just draw rectangles.
also, it's not really redrawing anything as neither step is drawing. the point clouds appear in 3d space just like you'd take a photo, and the revit wall element is a modeled thing you manipulate. If there's really any duplication of work it's that I'm taking field measurements (barely any compared to traditional methods of capturing as-builts) and then I'm taking point cloud measurements... but you know what they say, measure twice, place a wall once
We have a third-party company that provides LIDAR scans of existing projects for us. We have to be very specific about the goals of the scanning and what we intend to produce from the scans to make sure we get what we need. We do our own CAD/BIM modeling from the scans; old buildings are typically not square and can have some funky-ness due to settling over time, construction/installation errors, weird owner-performed repairs over time, etc. and we prefer to make our own determination on how that is approached when modeled/drafted. Having point clouds has helped us reduce the initial drafting time (draftsmen can get up and running before a site visit is performed) and we end up having a fairly comprehensive record of images showing existing conditions. Typically generally you always miss something when photographing. We also do on-site measurements just to get a double-check of what we are seeing in the point cloud, especially in high detail areas.