Renovations: best way to input existing plans

[JR5801]

Hello,

I was wondering what the best way (most efficient) method is of inputing existing pre-renovation models.

Currently, I go through an existing house measuring each room, I measure the outside of the structure marking down all doors windows etc. I then use a guide layer to draw 2D polygons using direct entry of the measurements obtained on site for each room. I then use them as guides to draw walls. This 'builds' my existing or 'before' structure that I can then alter/add to. I use the exterior measurements to act as a guide for the overall footprint of the structure.

Does anyone have a more efficient method of reverse engineering the floor plans of an existing structure? It is rather cumbersome doing it this way, and so far has always required returning to the site to confirm measurements for fine tuning.

Is there also a way to tell a wall to be x" away from another wall? Presently I use the tape measure tool to check dimensions when done, then move the walls the required amount.

[CipesDesign]

Jeremy, welcome to the club! Someone else may have a magical solution, but I a strongly suspect that the way you are doing it is the way we all do it (of course with minor variations). Another good case for hourly fees, I think!

[Delmer]

I can't say this is the best way, and its not so different from yours but here's what I do:

Same as you, do as-builts hoping the building is somewhere close to true -you can run a tape diagonally from corner to corner to check for discrepancies.

When inputting I use a couple of very short walls and copy them to appropriate offsets (drag a copy, snap it to a wall, ctrl m, tab, input #, enter) till all walls are in place. If you think there is a standard such as 1/2" drywall throughout you can factor that in so your walls are just stud thicknesses. Then go around connecting all the wall pieces.

When laying out additions or renovations it is prudent to limit (as much as you can) the places where you dimension off the existing. If you can pick just one or two spots, say an existing foundation wall, and then restrict all other dimension strings to new-to-new construction it makes for less headache. Anywhere you have to dimension back to existing construction throw in a V.I.F. (verify in field) note.

This is a good topic though, and I am interested to know what others do.

[Delmer]

I have had the opportunity to have someone measure while I input directly to a laptop. If the site is a ways away from your office this sure saves time in the long run. You inevitably run into those two walls that are 7 3/16" apart and you don't know where to make up the slack.

[Travis]

I've generally combined the Guidelines layer jeremyw describes with the laptop in the field Delmer likes.

I do strongly agree with the suggestion to dimension from only one or two existing points. Never trust someone else's "true".

Another point, other than the wall(s) adjacent to new construction, I generally measure to "center" of door/window openings and intermediate partition walls. It's often useful to see where they fall approximately, but they're not worth much of the client's money to have precisely located on the plan. So I don't sweat being out a little here and there. Just be sure to not drop in dimensions to these approximations AND I always include a Do Not Scale notification on the prints.

[jfmarch]

since we use laptops, we have recently begun doing as built plans on site. it saves alot of time. its good for simply projects where a record of your field notes is not as important, but since it is put directly into the computer it does not matter. we have a little rolling counter height table that works well on flat floors, and several batteries for non power facilities...

[jmartinarch]

being new to VW and using objects as opposed to simply drawing lines, how are you guys typically representing walls? For instance a 2x4, is 3.5" and on an interior it may have 1/2" or 5/8" gwb. Do you show with gwb or just stud thickness?

[Delmer]

Just the stud. That's what the framers need to dimension to. Everyone else measures off that. I once worked for an architect who thought the multiline capacity of walls in Archicad was such a great feature that we did a few sets of plans using it. Though you would think that that would allow you to figure out tile patterns etc. it was just chaos. Leaving the detail items for larger scale detail drawings saves a lot of time and confusion.

[Kevin]

quote:

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Originally posted by jm98499:

being new to VW and using objects as opposed to simply drawing lines, how are you guys typically representing walls? For instance a 2x4, is 3.5" and on an interior it may have 1/2" or 5/8" gwb. Do you show with gwb or just stud thickness?

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This is a good question. Of course you would use the wall tool to draw the wall as opposed to drawing lines.

I used to draw my as-builts with all existing walls shown as stud only. But I would often have problems in coordinating and compensating for the thickness of finish materials.

Recently I have switched to drawing existing walls with cavity lines to show the actual wall finishes. Since my field measurements are to wall finishes, it has made drawing the as-built easier with fewer mistakes.

[Kevin]

quote:

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Originally posted by jeremyw:

...Is there also a way to tell a wall to be x" away from another wall? Presently I use the tape measure tool to check dimensions when done, then move the walls the required amount.

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The "G" key will set a datum point. With your wall tool selected, move it to the point that you want to offset from. When you hit the G key it will set a datum and your menu bar values will turn to zero.

You can then drag your cursor to the location you want or you can imput the offset dimension directly into the menu bar.

[jan15]

I'm very happy with the method I use for as-built plans, which I often draw in the field with a notebook. It's very fast, but it doesn't involve the Wall tool. I draw only rectangles, entering X and Y coordinates on the numeric keypad as I draw. For rooms that aren't simple rectangles I draw their constituent rectangles and then Clip Surface to make up the shape of the room. At every door I measure the wall thickness and the opening width, which gives me another rectangle, and I use those door rectangles to locate rooms with respect to one another.

I draw all those rectangles and polygons on a layer that might be used later for area calculations, floor poche, or ceiling plan. But I also Copy them and Paste-in-Place to another layer, where I Select All and Add Surface, leaving a complex surface representing all the interior space. Then I draw the exterior footprint of the building, set its line thickness and fill as I would for walls, Send to Back, and Clip Surface to subtract the interior space from it, then delete that interior space object, leaving only poched walls. Then a thinner line rectangle for each window, which is clipped from the wall and left in place.

[JR5801]

WOW!

Some really great ideas. Thank you for the input. The small walls method never occurred to me. 'G' as well. I particularly like jan15's technique of using rectangles in doorways. So simple, yet it provides alignment, wall thickness and door position in one step. I have already used some of these ideas in my work.

Thanks Peter for the welcome, it is nice to see a forum that actually works.

VIF all the way!

[Kevin]

quote:

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Originally posted by jan15:

... At every door I measure the wall thickness and the opening width...

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What method do you, or anyone else, use to measure wall thickness. Doors typically have casing which precludes direct measurement.

[Travis]

Generally the jamb is very nearly the same thickness as the wall behind it.

If you can't see the jamb/casing joint, just make parallel lines on the floor (use straightedges if needed) that extend from inside the opening to beyond the back of the casing. Measure the distance between the lines in the opening and subtract the combined distance from each line to the face of wall out beyond the casing.

Good luck,

[jan15]

Or you could make a giant caliper, with offset jaws to reach around the door trim.

I did that a long time ago, when I was surveying a lot of historic buildings.

I made a sliding caliper, which was very long because it could measure walls up to 48" thick (in case of double masonry walls with furring), and could measure a wall two feet back from the opening (to avoid the thickening of some old plaster walls at corners and at framed openings), and so it was awkward to carry around.

But a divider-type caliper that would work for most walls could be made out of thin plywood or maybe even foam core board, and be small and light enough to carry around while taking field notes.

[CipesDesign]

The other point (and I think it was already kind of made earlier in this thread) is that there are always things that don't exactly add up. Usually, in a whole house, if things are working within an inch or two I am fairly satisfied. There are many reasons for small discrepencies in as-built dimensions, all of which compound on one another for sure. The main point is that the majority of the time we end up understanding the structure well enough to determine which walls are bearing or non-bearing, where the major point loads land, etc, etc, AND to convey on the plans which areas need to be paid special attention to by the builder.

[ 03-30-2005, 12:48 AM: Message edited by: CipesDesign ]

[Kevin]

jan15; You have me smiling at the thought of you carrying around this giant caliper. That is a great idea.

Peter's point of things not exactly adding up is why I am so concerned over wall thicknesses. I come from the idea that the as-built should be as near perfect as possible as I am basing my new design upon it.

I always find that once I draw the building, there are always discrepancies. Several have said that they draw on a notebook in the field and I agree. If you don't draw it on site, then you will have to come back later and make additional measurements to finalize your drawing.

I will be thinking of Jan15 and his giant calipers for some time .

[CipesDesign]

Kevin, if your clients are willing you should have the builder (or you???) go over and do some exploratory surgery. In many cases I have found there no replacement for it. Sometimes simply drilling one hole through the drywall (or plaster) will reveal what you are searching for.

I also agree that the whole point of the exercise is to 'get inside the head' of the original builder. However I always know that there will have been possibly numerous attempts by semi- or not-at-all pro's to remodel. This leads to things like double and triple layers of 1/4" drywall to cover wallpaper, walls furred out to seemingly random dimensions to accomodate drain lines from above, etc. etc.

I also have a clause in my contract that basically says:"During the process of remodeling previously unknown conditions will be uncovered, and they will need to be dealt with..."

PS: Jan, have you considered mass-producing the giant wall calipers? I could see a TV ad for it: order now and get a second one for free! LOL

[defjef]

In measuring exisiting buildings I try to use an dimensioning accuracy of 1/2" perhaps 1/4". Frame construction is rarely more precise than this. If you can measure between several rooms for an overall dimension, wall thickness can "reveal" themselves to a resonable accuracy. Because walls may be out of sqruare and out of plumb this level of dimension precision is usually acceptable. The Jan15 meathod is an excellent approach to drafting up an existing condition. You can even use his retangles as guides set on another layer or even deleted when on the same layer to lay walls, doors and window objects on.

An overall exterior dimension can also be useful in working out the proper interior partition relationships, You may have do so some fudging on your drawing, but this is no less accurate than the actual building itself.

[jan15]

Kevin,

I think of Sketchup as the fastest, least encumbering way to do any kind of non-detailed but dimensionally accurate drawing. As the amount of detail increases, Sketchup gets slower relative to other software. So I always start out in Sketchup, designing rough massing. Then when it gets slow, I export to DWG and switch to VectorWorks (except that at the moment, hopefully for a brief moment, I'm forced to use AutoCad, which I think of as the slowest, most encumbering way to do anything).

The fact that Sketchup does 3D just as fast as 2D is an extra bonus. It's especially advantageous when surveying. When I use a clipboard and pencil, I'm pretty good about noting vertical dimensions on my sketch plan (written along diagonal lines pointing to the place that's at that height above or below the floor). But when I survey using VectorWorks on a laptop, I tend to forget to note vertical dimensions. And I don't do VectorWorks 3D at all (too lazy to learn). So now I use Sketchup, and I come home with a complete 3D model of the overall geometry of a building, inside and out, and I can start right in on the remodelling design. I put the ceiling and roof on a separate layer so I can turn them off while working.

I export 2D views from Sketchup and import them into VectorWorks. That's an easy and trouble-free procedure. It can export any view -- plan, section, elevation, isometric, or perspective. I've had no success at all going the other way, though. DWG files imported into Sketchup, whether they started out in VectorWorks or AutoCad, always end up causing me trouble. But that's o.k. because Sketchup is the first step.

[Kevin]

Thanks jan15,

I love SketchUp. I just did not see how I could use both SU and VW. Perhaps I need to play around with SU some more and see if I can replicate what you are describing.

Earlier you described how you use rectangles to draw your as-built plans. Are you talking about doing this in VW or in SU?

[JR5801]

I thought you might like to see this:

Dr. Calipio and his Architecture co-op student move the new experimental mega-caliper into position to get accurate external measurements of a clients Malibu beach house.

Dr. Calipio is quoted as saying "This could be the end of V.I.F. and Do Not Scale notices on drawings of the future, we are very excited about this work. We even have city block size calipers in the works. It seems to be a fully scaleable technology with no end in sight" (April 1, 2005)

[Delmer]

ROFL

[jan15]

Jeremy,

I'm very interested in the idea, but I don't understand the picture. It looks like they're getting ready to set up a volleyball net. How does that thing function as a caliper?

[JR5801]

I wish I knew.

It is too high tech for someone of my lowly pay grade to figure out....