Free Loft Conversion Design Tool

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Hello all

I'm about to build a dormer on my roof when I do a loft conversion... now I have only done a couple of extensions and do have people to help me if I get stuck.

I have spoke to the building inspector and asked if I need drawings doing by an architect for the conversion and dormer. He has said no as he will advise me on what size timbers I need to use for the new floor joists and any other queries... I just have to send a drawing in the council planning deparment just incase...

I was hoping to do this myself on my laptop but not sure what free cad packages are out there and which ones are the best? Any ideas?

many thanks

Dave
It helps if you state which OS you use. The following are free as in Open Source/Free Software:

QCAD2 (QCAD3 is non-free): reliable if utilitarian 2D CAD. Easy to pick up (I did my extension in it): http://www.qcad.org/
Available for Linux/Windows/MacoS/Solaris/FreeBSD

FreeCAD has recently been made Free Software and is 3D: Not yet used this one but it looks very good http://sourceforge.net/apps/mediawiki/free-cad/index.php?title=Main_Page Available for Windows/Linux/MacOS

Blender can be used for 3D CAD and modelling but the interface is pretty funky (designed for animation, not architecture) so it takes hours to get anywhere: http://www.blender.org/
Available for Windows/Linux/MocOS/FreeBSD

BRLCAD is a fancy 3D solid modeller, but I found it impossible to drive. Very 1980s. http://brlcad.org/ Available for Windows/Linux/MocOS/Irix/BSD/Solaris (!)

Don't bother with PyCAD, it's not done enough to be any real use yet IMHO.

There are various programs which are not freely-licensed but which can be used cost-free: My favourite is
Sketchup: which has a genius 3D interface, but is only available for Windows/MacOS http://sketchup.google.com/
Very good indeed for quick models - rather less good for detailed drawings (v7 has DWG support - they took it out of the v8 free version).

Sweethome 3D is nifty but is really for interior design, not real CAD. http://www.sweethome3d.com

There are many more, mostly with some kind of semi-crippled free download, and you get to pay for useful versions (e.g. http://www.cadlogic.com/products/draftit/), Some of these may be adequate if you do not have complex requirements, but those above are the ones I know something about.

Free DWG support generally is very thin on the ground, because the buggers at AutoCAD and the Open Design Alliance make it really hard to supply. LibreDWG is fixing this and is now quite useful, but is not yet used by many programs.

We have had a CAD thread on here before but I can't find it now.
I found DoubleCad to be ok and have used it to design the extension to my home. www.doublecad.com

There is a free version that has no limitations and has DWG and DXF support (very simlar to autocad LT but free).
If you hate learning new programs Google sketchup is pretty good. Has a few quirks but it's pretty good for dashing off a quick 3d sketch. Main issues I find are to do with annotating drawings and printing to scale but both are possible.
If you have kids in education you can get autoCAD for free.
Posted By: borpinIf you have kids in education you can get autoCAD for free.

How, please?
Check on their website for something like education. You need to register with an academic type email address them you get a key via email. Software4Students is another site as well. I will check at home tonight for a better link.
Bear in mind that AutoCAD has a pretty steep learning curve. I've been using it for around 20 years and the quirky interface and the odd way that Autodesk do things in their software still bugs me. Incredibly powerful CAD package though, but really aimed at people who can already understand how to produce technical/engineering drawings with a pencil and paper to the appropriate standards.
Yes, Draftsight is a true full-featured Autocad clone (2D only) and it's free, from Dassault Systemes, who are setting out to challenge Autodesk (Acad's manuf) for the top slot. Draftsight is intended as just a petty annoyance/challenge in their own backyard to Autocad, but they're doing it seriously, with excellent online tutorials and support etc, rare for a free program.
We have noticed since DS came along the cost of ACAD LT subscription has dropped significantly. We are trailing it alongside ACAD LT and so far have found only one or two issues none of which are insurmountable.

J
Wd you say DS is equiv to Acad LT, or to the 2D portion of full Acad? How have you found DS's online tutorial/blog/support?
Posted By: wookey "We have had a CAD thread on here before but I can't find it now."

http://www.greenbuildingforum.co.uk/forum114/comments.php?DiscussionID=3978

where Wookey writes: "...so it's fair to say that Sketchup is much easier to drive, but that only comes for Windows (and doesn't work very wellfor me in wine, although it is supposed to)."

Works usefully, though not perfectly, for me under Wine. Some textures are a bit odd, cursors sometimes had a black rather than transparent background and sometimes lines which are deleted don't disappear until you close and reopen the drawing.
Posted By: fostertomWd you say DS is equiv to Acad LT,

Seems so but have not used full CAD for years...

J
Just downloaded DS for Ubuntu and it just works. Brilliant! Thanks for the pointers guys. Just got to learn how to use it!!!
I've had cause to use LibreCAD last week, which is actually just QCAD2 repackaged with Free icons, fonts, and Docs. So it works exactly the same as QCAD but has funky green icons rather than old-fashioned (but clearer IMHO) red ones.
http://librecad.org/cms/home.html

This software was previously packaged as 'CADuntu' for a while.
Have you tried DS? How do they compare? Initial comparison of reviews seems to show that DS can use AutoCad files LibreCAD uses its own format.
I will check out DS. I have been looking for a free bit of software for my personal computer.

I use AutoCAD LT and find it great for anything 2d and archectural.

I used to have a full 3D Autocad, and found it fairly hard work to make detailed 3D models, so now just rely on GoogleSkethup to throw out quick 3D concepts and lay stuff out in detail in 2D.
I haven't used DS. (It's not FLOSS, and I avoid using non-free software as much as possible - i.e whenever I have a practical choice). LibreCAD uses DXF which is the old AutoCAD standard format. It doesn't use or support DWG (the new AutoCAD format) because AutoDesk deliberately make it extremely difficult to do so (see whinge above).

If you need/want DWG _and_ FLOSS you have exactly one option: FreeCAD. More will be along soonish as LibreDWG gets incorporated into packages.
It's absolute rubbish to refer to DWG as a new file format. I've been an AutoCAD user for more than 25 years and in all that time DWG has been the default file format, in fact I'm reasonably sure that even the very first version of AutoCAD used it. The first version of AutoCAD I used was the DOS version2.5 Release 7 back in the mid-eighties (running on a 20 MHz 286!) and DWG was the standard file format back then.

I agree that Autodesk have deliberately kept the file format closed, but as pretty much all CAD systems can read each others files, at least at the 2D level, it's not often that I've had occasion to revert to saving files as DXFs.

I'm not praising or supporting AutoCAD in any way, BTW, as even after 25 years of using it I still think it is has a pretty odd user interface and it certainly takes a heck of a long time to get proficient at using it.
I used SolidWorks yesterday, and after 12 years of using TurboCad I found it very alien. Seems each of these packages has different ways to input angles, dimensions, thickness and so forth. If I want to draw a line 10 units long at an angle of 15, then I just want to do that, I do not want to have to worry about relative or absolute coordinates. Having come from a manual background it all comes down to compass and rule, about the purest form of geometry there is.
And why is printing out so fiddly with CAD programs with their scaling, views, paper sizes and disabling printer defaults (I do know the reasons really)
I never print from Autocad these days, but 'print' the paperspace sheet to file as a .pdf (precisely, print to CutePDF as if that application is the printer) and then print paper copy from the .pdf file. The latter is then as reliable and straightforward as from e.g. a doc file, and the image quality is greatly improved, somehow. The .pdf conversion must sharpen edges etc.

.pdf file sizes are generally small and emailable but sometimes, esp if there's a photo aka 'raster image' dropped onto the paperspace sheet, .pdf file size can jump to MBs, even if the raster image was only say 250kB.
Posted By: JSHarrisIt's absolute rubbish to refer to DWG as a new file format.

I think it rather depends on what you mean by DWG. The same extension has been used for ages but my impression is that AutoDesk come out with a new design which strongly affects the structure of the DWG about once every three years so calling "modern" DWG a new format is not much of a stretch. I suspect that at least part of the motivation for this is lock-in.

I worked on plug-in software for use in AutoCAD for a few years and finished up collapsing in a depressive heap. AutoCAD wasn't the cause but it really didn't help.
All I can say is that the architect send me a DWG file and DS opened it no bother and really that is all I need!
I believe just about every new AutoCAD release has added features to the DWG file format, right from the very beginning; it seems to have been a fairly continuous development process. I'd guess there are probably a dozen or so DWG variations by now, but all are backward compatible.

The same applies to the DOC format used by word, I believe, and probably a lot of other proprietary file formats.

The only problem I've ever had opening DWG files has been with Autodesks own products. AutoCAD 2000 pretty much baulked at trying to open some of the DWG files I had for some reason, whereas Release 21 seems fine with all of them.
Agree about the non-intuitive nature of AutoCad, it's what put me off it at the outset and why I went to and stuck with TurboCad. Granted my requirements are basic compared to someone drawing a complex engineered component, but even guys I know who do use CAD for those more complex drawings say they've found TurboCad faster to get around than AutoCad once they've made the transition.

In my own use most operations involve little more than a choice of modes, a switching on or off of snap, the initial choosing of start point and then simply tabbing and entering values in e.g. length, offset, angle, etc. I can do the joinery drawing for a sash window in about 10 minutes; a set of three-elevation drawings for winder stairs in about half an hour. Add about 15 minutes for jointing details.

Mind you, knowing how software engineers find it impossible to resist the temptation to mess with something that is working perfectly well, my easily accessible TurboCAD Pro v8 will by now have evolved into something that is virtually impenetrable. And I bet you can no longer get a hard-copy manual with it either.
I note JSH's typically effusively-polite correction on the vintage of DWG :-). I am surprised; I really was under the impression that DXF was standard back in the day. But I've never used autoCAD so defer to someone who has. So where did DXF come from? Was is the exchange/export format, as opposed to the native format?

And you may never have had much trouble opening DWG files, but rest assured they are essentially inaccessible in FLOSS-world, so don't send them to people like me if you don't want a lecture on the evils of proprietary formats.
Posted By: JoinerAnd I bet you can no longer get a hard-copy manual with it either

Charity shops are a great source of technical books.

On TurboCad17.1 and it is really little different than 5, but that is probably more to do with the basic stuff I use it for.
Posted By: wookeySo where did DXF come from? Was is the exchange/export format, as opposed to the native format?

Came from AutoDesk in 1982, they publish the specs.
<blockquote><cite>Posted By: wookey</cite>I note JSH's typically effusively-polite correction on the vintage of DWG :-). I am surprised; I really was under the impression that DXF was standard back in the day. But I've never used autoCAD so defer to someone who has. So where did DXF come from? Was is the exchange/export format, as opposed to the native format?

And you may never have had much trouble opening DWG files, but rest assured they are essentially inaccessible in FLOSS-world, so don't send them to people like me if you don't want a lecture on the evils of proprietary formats.</blockquote>

Sorry if I was a bit blunt, I tend to react badly to definitive-sounding statements that seem wrong. The origins of these two file formats goes back to early DOS days, when AutoCAD was one of the first (maybe the first) professional CAD package available that would run on a desktop PC (prior to AutoCAD our CAD systems at work ran on a mainframe).

The DWG (literally "DraWinG") file format was the working file format that AutoCAD used internally, and contained a lot of information specific to the way AutoCAD works. The idea was to best use limited PC processing power (bearing in mind that just refreshing a view after a zoom on a simple drawing took maybe half a minute or so back then).

The DXF (literally "Drawing eXchange File) format was the default format provided with AutoCAD for transferring drawing files to other CAD/CAM systems. For example, our draughtsmen would draw things in AutoCAD, working with DWG files until the drawing was completed, then send a disc with the DXF file on it to the model shop for manufacture.

Over time, DXF came to be the fairly universal drawing file exchange format, which was pretty much exactly what AutoDesk wanted. AutoDesk probably dominated the desk top CAD market for years, right up until they got left behind by the development of the current crop of 3D capable systems, like CATIA and SolidWorks. I suspect CATIA has a bigger market share in AutoCADs previously dominant area of aerospace now; in my experience virtually all of the big aerospace companies use it pretty exclusively, which tends to drive other markets.

All of the major CAD systems use proprietary formats. AutoCAD would only run on a PC back in the early days with a licence dongle plugged in to the parallel port, they were that paranoid about their software being copied. This isn't surprising, as there is a massive amount of intellectual effort involved in producing a CAD package that can be qualified for aerospace, or even automotive, CAD/CAM.