When it comes to converting a set of blueprints into a framing design, it is often left to the lumber yard or truss manufacturer to establish the layout of framing members. All too often they simply pick a corner of the house and start the layout at 16” O.C. or 24” O.C. And while that might be fine for a building whose dimensions are equally divisible by 4’, that is rarely the situation. Always making this general assumption regarding layout can lead to numerous problems down the line and wasted material.
We like to create a full set of framing documents prior to ordering materials in order to identify problematic areas with the design and ensure that the correct materials are ordered. A preliminary set of drawing from the roof and floor system manufacturer before production is a must, so that we can have time to review them and request changes.
Problems arise because floor system manufacturers do not consider the needs of other sub-contractors when establishing layout. Here is an example from the most recent project we are framing:
The layout is 16” O.C. and was started from the left side, but because of the dimensions of the house we already have some problems. The areas highlighted in yellow indicate areas of the rim that will be very difficult or impossible to insulate. But there are other problems as well:
In this image we have overlaid the plumbing penetration from the bath tubs, showers, and toilets. As it turns out the layout causes a conflict with the location of two toilets. But the solution to all of these problems is actually quite simple:
Here we have shifted the layout so that it is centered on the foundation. By simply moving the layout 4” we have simultaneously made it possible to insulate our problem areas and avoid all of the plumbing penetrations. The added bonus is that we used 10’ less of I-joist material!