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Questions and Answers

We are not going to pretend, that these are all actual questions. Some are, others are ones designed to enlighten you about what we do.

At the end of these questions, we hope, you have a better understanding of what we do.

Door Jambs

What is a Door Jamb?

The Door Jamb is the Timber piece that surrounds the door when it is installed. On a Single or Double Hung Door, it is the piece the hinges are attached too. There are three pieces to it, both upright sides and a top horizontal piece connecting the two sides. One hung, the door stop is attached directly to the Jamb.

What is a Door Stop?

When referring to Pre Hung Doors, the Door Stop is NOT a metal piece that stops the door handle hitting the wall. 

It is a small piece of timber around 30mm wide and 10mm deep, pre cut the required length.

They are nailed onto the jamb in the position that will stop the door in the correct position. They also assist with sound and heat insulation.

What kind of Jambs are there?

There are two main types of Jamb.

Flat Jamb and Grooved Jamb.

Flat Jamb?

Flat jamb is in reality a flat piece of timber.

It is aprox the width of the wall (Timber and Gib), when in position, the Architrave is then placed over the facing edge and the gib, hiding the gap.

It comes in a number of configurations (this varies depending on size). Without door stop attached, with door stop pre attached and as a split jamb system.

The advantage with the Flat Jamb System is that it is highly flexible, enabling a wide range of sizes.

Groove Jamb?

Grooved Jamb is a system designed to reduce the need for Architraves (the piece of timber that connects the pre hung door to the wall, hiding the gap between). For the same door, it is wider than a Flat Jamb as it has grooves in it designed to enable gib board to slide into the groove, removing the need for Architraves.

Some prefer this Jamb for the look it provides, however the main reason it is used is the belief that it is cheaper than flat jamb as it dosen't need architraves. Unfortunately this is a false narrative, while it saves on architraves, it does cost more and increases the labour costs of install, gibbing and painting. It is also extremely inflexible as it is specially made and is only available in certain sizes.

What do you recommend?

Flat Jamb. For one very simple reason, it is flexible. Whether you need a jamb at 92mm or one as big as 280mm, it is possible with a flat jamb system. It is also easier to work with if changes need to be made and can be adapted on site.

I have an unusual size required, can it be done?

With Flat Jamb, yes, we can provide a precise, special size jamb.

What type of timber do you use, do you use MDF?

Firstly, we DO NOT use MDF.

The timber we use is New Zealand Grown Pine. Varying from untreated to 3,1 or 3.2 for external doors.

You saw you deliver Nationwide, it must cost a small fortune?

We have a strong relationship with a Nationwide Freight Company. To reduce costs, they will deliver to you local Trade Suppliers Yard (you will need to discuss with the merchant) or you can pick up from the depot.

Our Door System is unique and we are able to Flat Pack. Generally a houselot fits on a single Pallet and can be moved with a Trailer.

I have some more questions, what do I do?

You can email us at sales@prehung.co.nz, call us on 0800 400 790, or click the Lets Chat box and ask there.

We are seeking more questions for this section, so welcome your input.

Thank you.

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