Steel Detailing | Precast Detailing | Estimation

Tag: near face

  • THE USAGE OF NEAR FACE(NF) AND FAR FACE(FF) INDICATION ON SHOP DRAWINGS

    Near face (NF): Near face is a front view of the precast wall.

    Far Face (FF): Far face is an outside view or trowel face or table face of the precast wall.

    • Near face and Far face indication playing a major role on shop drawings to identify the component placing for factory people while manufacturing panel. (Refer Fig.02)
    • At initial stage we draw the panel footprint on marking plan and fix the panel view based on where the panel comes like inside or outside of the building.
    • In marking plan, we viewing the panels both inside and outside of the building because to achieve architect and structural aspects or requirements and to avoid some manufacturing difficulties.
    • The below mentioned details are used to fix the views for precast panels from marking plan.1. To View from inside of the building:
    • Good table finish will be on Far face.
    • Grooves, patterns, different profile design comes at outside of the building, so it will easy to assign profiles on far face of the panel and it will be on table face on factory. (Refer Fig.03 & 05)
    • For upstand or corbel to be comes at near face of the precast panels to avoid manufacturing difficulties.
    • If any bars connecting to in-situ at near face, we also view the panel from inside.2. To View from outside of the building:
    • For basement level panels no need trowel finish or good table finish on far face of the panel (Outside of the building). In this case we looking the panels from outside of the panel.
    • If panel have upstand or corbel profiles at outside of the buildings, we need to view the panel from outside to avoid manufacturing difficulties on factory. (Refer Fig.01)
    • In few cases, building inside is fully balcony and outside side is partially inside of the building. So, this kind of scenario we viewing the panel from outside of the building due to panel finish. (Refer Fig.04)

    General:

    • For multi-storied buildings, we follow the same elevation number for same set-out from lower level to above levels.
    • The starting level of panels we will fix viewing direction as per current level architectural and structural aspects.
    • Some cases the lower-level panels come at inside of the building and above level panels comes at outside of the building. In this case we viewing the panels same as per lower levels but we flipped the above level panels for manufacturing purpose.

    Advantages:

    • Drawing study is easy for factory people.
    • It will reduce the time delay of manufacturing the panels.
    • It will also avoid the manufacturing difficulties and Errors.

    Fig.01

    Fig.02

    Fig.03

    Fig.04

    Fig.05

  • The Signficance of the “Mould” Face in Precast Panel Detailing

    The Mould Face

    This post attempts to explain the following two questions, for those starting to learn the precast trade:

    • A lot of fancy words are thrown around. Near face. Far face. And mould face. What does it all mean?
    • How should shop drawings be marked vis-a-vis the mould face, and why should they be marked as such?

    What is a precast panel?

    These my friends are precast panels:

     

    What panels look like.

     

    • You can build things quickly and cheaply, if you build with precast panels. Your other option is to fabricate on site. The problem with this is that it: (i) is more expensive, and (ii) the construction is a lot slower.

    What is the mould face?

    • First you have to understand how the panels are “fabricated” (i.e. how they are made). Concrete is poured into a mould, on a table. It looks something like this:

     

    Showing a panel on a table, in its mould.

    So then what is the near face / far face / mould face?

    • The near face is the side of the panel which is exposed to the air. This is the face of the panel which you can see.
    • The far face (or mould face), is the face of the panel which is lying on the table.

    What is the significance of the mould face?

    • The mould face has a smooth finish (or should have one).
    • You do not want a building which has the ugly face of a panel exposed for everyone to see. The architect will be baying for your blood, and moreover it is a very costly remedy. Some precasters, in order to avoid this problem, “trowel” the near face (i.e. the face which is exposed to the air). “Trowelling” is when you smooth the surface of the panel with a tool so that it looks nice.

    When you draw a panel, you want to indicate on your drawings that the mould face is on the building exterior.

    • Why? So that the smooth side is seen by people and the ugly side is hidden from view.
    • “But won’t people on the inside of the building also see the ugly side of the panel?” you ask. Not necessarily. Most of the time, the panel is not visible on the inside of the building because the architect will put up plaster or there will be something hiding the panel from view.

    Standard Shop Drawing Practices

    • People draw elevations assuming they are looking at the near face first, rather than the far face.

     

    This diagram should certainly clear things up for you:

     

     

    Shows the near face and far faces on the marking plan – also notes where the exterior of the building is.

     

    I hope you learned something. Any questions, please ask.