SST_1807 – Creating And Managing Details

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For any construction project, details are an important part of the drawing set. It can take a long time to fully detail a project, so let’s look at how to draw a detail and some strategies for speeding up the drawings. We will look at importing details, applying the principles of detailing, creating details, creating multi-use details, and using details from your library.

Contents

 

Beginner Topics

Principles of Detailing – 4 D’s of Detailing

Deflection
Deflection, as its name implies, is where you prevent the water from entering a building by deflecting it. This can be accomplished by having roof overhangs, overlapping materials, or flashings (flashings, which are typically made of metal, help the water to deflect over other components).
You might be able to deflect water from a building by having a roof overhang. In the image below, you can see how much of the building is protected from the rain because of the roof overhang.
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You might be able to deflect water away from the building because the components overlap each other. In the image below, you can see how the cladding is deflecting water away from the foundation.
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A classic type of deflection is a flashing. These are essential for deflecting water away from a building.
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Drainage
If there is a chance of the water getting behind the cladding, drainage will allow the water out. Some cladding systems are specifically designed with the assumption that water will penetrate the cladding but will drain out of the wall assembly.
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Brick cladding often has small gaps or openings that allow some moisture through. Bricks are also permeable and can allow a small amount of moisture through in severe weather. Brick cladding systems are therefore designed specifically to allow the water to drain out through openings at the bottom (open vertical joints in the brickwork).
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Drying
Some wall assemblies are designed to allow airflow through the cavity to improve drying. Some systems, such as brick cladding, are designed based on how the sun and wind will dry the exterior skin of the brick.
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Durability
In terms of hierarchy, durability is the last stage. If the cladding system is such that deflection is not possible, drainage is not suitable, and drying is not available, then the product must be durable enough to withstand being occasionally wet.
Durability is an important lesson learned from leaks in buildings. The materials used in timber buildings cannot withstand being wet occasionally; the wood begins to rot.
The products that you use in your detailing must be durable. This might mean that you will need to check your timber treatment or that you might need to check the type of metal that you want to use.
 

Principles of Detailing – 5 Physics Principles

Gravity
Water ingress due to gravity occurs when the water moving down the face of the building finds a sloping path that allows the water into the building. This usually occurs because of the lack of a deflection device such as a flashing.
In the image below, you can see the water running down the face of the building. Because there is no flashing, the water continues to run down until it reaches the window joinery. At this point, it can find its way into the building and cause damage.
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The solution is to ensure that materials are correctly lapped and that flashings are correctly installed. Correctly installed deflecting devices such as roof eaves, water barriers, and flashings will prevent this. This image shows the same window joinery being protected from the water by a flashing (which causes the water to drain away).
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Pressure Differential
The pressure differential is the difference in air pressure between the inside and outside of the building. If the pressure on the outside of the building is higher than the pressure on the inside of the building, then this pressure differential can drive water up and into the building. This can occur even when there are very small gaps in the building cladding.
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The solution is to provide air seals, a wind barrier, or pressure equalization. In this case (window detail), the typical solution is an air seal.
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Kinetic Energy
Kinetic energy refers to the energy of wind-driven rain. The wind can drive rain a considerable distance into openings and even up roofs. A classic problem with wind-driven rain is when rain travels up a roof slope and into a building.
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In this image (0017), you can even see that rain is being driven up under a flashing and into the building. The flashing deflects falling water away from the building, but the wind can still blow the water up the trough of the roof and under the flashing. In this case, the flashing will help protect the junction from the wind, but not completely.
The solution for this particular problem is to use a stop-end on the roofing.
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Surface Tension
Surface tension is similar to capillary action. It occurs where the surface tension of water allows it to move horizontally on the underside of services. This often occurs in situations such as roof soffits, the underside of a window sill, or any surface of a building that changes from a vertical edge to a flat underside.
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To solve this problem, make sure that you have a break in the horizontal surface. This is often called a drip edge. The water will find it impossible to travel vertically upwards, so the drip edge will cause the water to fall away.
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Capillary Action
Capillary action is caused by water tension that allows water to pull itself upwards through small gaps in the building. Gaps less than 6mm wide are susceptible to capillary action.
In the image below, two areas have been highlighted as being susceptible to capillary action. On the weatherboards, capillary action can allow the water to travel upward where the boards are close together but not forming a sealed joint.
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In the second area, capillary action can allow the water to be drawn across the top of the window and inside the building.
The solution to capillary action is to ensure that your gaps are wider than 6mm. In many cases, an air gap will solve the problem, as shown in the image below. For the weatherboards, two overlapping gaps will prevent any capillary action. In the window detail, you’ll notice that there are gaps at the head of the window and a corresponding gap on the window joinery. The combination of these two gaps creates an area that is more than 6mm, thus preventing capillary action.
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Here is a summary of the ways in which water ingress can be controlled:

Water ingress caused by: Solution
Gravity Deflection
Overhangs
Sloped surfaces
Flashings
Drip edges
Cavity construction
Capillary Action Clearance between surfaces
Gaps
Weather grooves
Drip edges
Surface Tension Weather grooves
Drip edges
Rebates
Kinetic Energy Flashings
Facings
Seals and sealants
Deflection
Pressure Differential Air seals
Pressure equalization
Wind barrier
Air barrier

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Importing Details

The easiest way to create your details is to import them. You can import your details from an existing project in Vectorworks, from PDF drawings, or from a manufacturer’s website. We will deal with inputting your details from an existing project later on when we talk about creating a detail library.

Importing PDF Details

Some manufacturers and building codes have details that you can import through PDF drawings or documents. For this example, I use a local building code from New Zealand and the Acceptable Solution document (E2/AS1). The document shows an acceptable solution for achieving building code compliance for weather tightness. It includes many details that are suitable for light timber frame construction. (https://www.building.govt.nz/assets/Uploads/building-code-compliance/e-moisture/e2-external-moisture/asvm/e2-external-moisture-3rd-edition-amendment7.pdf)

  • In this example, I want to import a barge flashing detail. This is common, and instead of redrawing the entire detail, I could just import the PDF.
  • I have found the required detail on page 81 of the PDF. Checking carefully, I find that this is actually page 88 of the PDF, although the page number shows 82.

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  • Now that I know my page number, I can drag-and-drop this PDF into Vectorworks.

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  • Choose the page number required.

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  • Ensure that you calibrate your detail. You can do this by selecting a PDF page and scaling it. Use Modify > Scale Objects… from the Menu bar.

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  • Use if for creating details in your documents only after calibrating the detail. You can either crop the PDF and make a viewport from that, or you can create a viewport on the PDF without cropping it.
  • Draw the required shape for the viewport crop. In this case, I will use a rectangle because it is easy and quick.

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  • Create the viewport and place it on the correct sheet layer.
  • Turn on the drawing label and ensure that you give this detail its correct number.

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  • You can do this with several details to create a detail sheet.

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Importing DXF/DWG Details

Importing PDFs can work very well, as long as you’re not concerned about the graphic style of the details. For example, you might not like the line weights, the text font, or the dimension standard. An alternative might be to import the detail as a DXF/DWG file. Many manufacturers include details in this format.
Vectorworks can import a wide variety of file formats. Two of the most common file formats for importing drawings are DXF and DWG. There are slight changes between these two file formats. Vectorworks imports them using exactly the same importing engine. I will treat these two files as interchangeable.
Some manufacturers even have details in the Vectorworks or MiniCad format (Vectorworks’ former name). If you see files listed as .vwx or .mcd, you do not have to import these files, you can just open them. This makes it easy to import the details from these manufacturers. All you have to do is open the files, then copy and paste the required details from these into your work.
Many manufacturers have details in the DXF/DWG format.  These files have to be imported using the DXF/DWG import command.
Never import DXF/DWG files into your existing project. Always import these files into a new, blank file.

  • Go to the Menu bar.
  • Choose File > Import > Import the DXF/DWG or DWF…

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  • This opens the import DXF/DWG or DWF dialogue box. I usually don’t use this dialogue box because it hides the import options and doesn’t remind you to change them. Using the wrong import options can make your details unusable.
  • You can import one or more files or you can import all the DWG and DXF files from a particular folder. Sometimes when you download a manufacturer’s details, you can download a folder with all the details inside.

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  • Click on the Choose Folder… button to select your downloaded files.
  • Navigate to the required folder.
  • Click on the Select Folder

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  • Ensure that you have the correct folder and path shown in your dialogue box.
  • Then click on Set Custom Options… This is the option that is often missed.

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  • Check your primary settings to ensure that you are importing the details with the correct units.
  • Since I require 2D details, I’ve chosen the All 2D
  • I also want these details to be set at a scale of 1:5, so I’ve also selected that under my Model Space

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  • Check all of the other options for graphic attributes, objects, and location.
  • If this is a manufacturer that you commonly get details from, then you can click on the Save… button to save the settings. Vectorworks will store the settings on your computer so that you can recall them the next time that you import information from the same manufacturer.
  • Click on the OK button to return back to the import dialogue box.
  • Click on the OK button once again to complete the import.

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  • This action can’t be undone, but since we are importing into a blank file it doesn’t matter.
  • Click on the Yes
  • Vectorworks will give you a report on the progress.

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  • Here are the completed details.
  • This method tends to create a lot of design layers. Each imported detail is placed on its own design layer.

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  • Usually, the information in the design layers is on top of each other. If you spend some time you can group each detail and move them so that they are separated.
  • Another option, when you import the DXF/DWG file is to choose the destination option Symbols under Current File. This will import each detail and convert it into a symbol.

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  • When you check your Resource Manager, you will find that the symbols have been created and stored there. This can make it easy to move the symbols to the correct design file or to your library.

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Drawing Details

This is not the only way to create a detail, but it has proved to be a useful way. I start with the structure. If I am drawing a wall section, I will start with the foundation slab.

  • In this example, I will start with the wall framing. I am using a freehand sketch; you can follow the same strategy with Vectorworks.

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  • The next layer of information is the building wrap.
  • Notice how the wrap is shown away from the framing. This makes it easier to distinguish on the printed drawing.
  • In reality, the building wrap would be tight against the framing, but on the drawing, that would make it difficult to see.

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  • The next layer of information is the cavity battens.

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  • After the cavity battens, the wall cladding is drawn.

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  • Finally, notes, dimensions, and arrows are added to annotate the detail.

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  • It is often easier to sketch details freehand before drawing them in Vectorworks.

 
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  • In this example, I’ll draw the same detail using Vectorworks. Instead of drawing each piece of timber individually, I have a library of detail parts that I can select from (see below).
  • Starting with the Resource Manager, I have located the correct size of timber for this detail.

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  • Using a library object makes it easy and fast to draw all the pieces of timber.

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  • Use a polygon to draw the building wrap. I usually draw the polygon directly on the face of the framing and then offset it.
  • Change the line weight and line style to suit your drawing style.

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  • Add the cavity battens. Using symbols will speed up this part. Has a locus to help locate the batten 2mm (1/12″) from the building wrap.

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  • Add the cladding.

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  • Here is the cladding with the notes. This is a detail from a real project.
  • Once you have created the details, you can then group them or you can turn them into symbols and store them in your library, which is the next topic.

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Intermediate Topics

Creating a Detail Library – 1 (Detail Parts)

I have noticed that it’s quite common for details to change from one project to another.
For example, when I worked for a local architect for many years, it was often difficult to use exact copies of the previous project’s details because the building designs changed. As this architect didn’t like to use standard details from a PDF download or imported DXF/DWG files from manufacturers, our details would often need to be drawn from scratch using basic elements and components. I still have many of these parts in my library. These would be components such as pieces of timber, steel sections, flashings, nails and screws, and cross sections of cladding materials.
This means that when it comes to creating a detail, I do not have to draw everything. I can assemble the detail from components. These components are stored in my Resource Manager, making it easy to find them.
There are a couple things that I do to make it easy to find my detail components.

  • There is a separate folder for each type of detail part in my library file.
  • The insertion point for details is consistently placed in the same part of the symbol.
  • The detail parts are created with the line weights and line colors that I require.
  • The detail component symbols are named accurately and concisely to make them easy to find.

Here is an image showing my timber library:
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I also create folders in my library for detail parts. These are detail parts that I use on a regular basis. Including things such as steel, skirtings, flashings, etc.
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Creating a Detail Library – 2 (Referencing)

 

Advanced Topics

Creating Multi-Use Details

When I first saw this technique, I was really impressed. Let me explain how this works. Let’s say that I have a common foundation and wall structure. In my example, I will use a 100mm (4”) concrete slab with light timber frame construction. For the work that I do, this is extremely common. The cladding is not common. Sometimes we use sheet material (plywood), sometimes we use weatherboard (siding). This cladding is sometimes on a cavity, and sometimes not.
When it comes to creating details for these systems, we end up with a lot of details. Substantial parts of these details are identical (wall framing, concrete slab, and fasteners). These details have to be stored so that they are easy to find.
The technique that I’m talking about is to have the same detail with different claddings on different classes. This means that you have one detail that will cover many of your different plating systems. To change between one cladding system and the other, turn off the class of one cladding system and turn on the class of another. When you do this, not only will the cladding system change but all the notes will change as well.


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