Warning: The height of the boards is critical: you want the top of the rear board to be completely horizontal and 15mm below the height of the lintel. I have a house built in 1790 with 4 fireplaces. One of those being what I have heard called a "Walk in" fireplace. The opening is basically 4 feet wide and 4 feet tall. So you can imagine the flue is huge as is or was the flue housing.

This is not always obvious from the ground, but could be a problem. Be sure to get a quote before any work is carried out. Because the stove is directly connected to the flexible flue liner, the closure plate isn’t required to be sealed in the same way as a register plate. In the stove room finish the whole job: hearth down, line fireplace, slide closure plate in, plastering, stove in place, cup of tea etc. Closure plate installation here: Wood burning stove in a fireplace connected to a chimney liner

Register plate for a wood stove

You will need to paint the surface of the inside walls of the recess and one side of the cement board with a PVA mix (3 water to 1 PVA). This is very important as without this stage the bond between wall and board may not be good. Measuring from this center line and on the line 1” in from the front, mark at 1/2 the measurement #1 in both directions (in the example, we would use 18” from each side of the line. Then make another mark at 1” past that line (or 19” from the center line). In either instance of a fireplace balloon or a glass door, you’ll have to measure your fireplace! The DIY Route

What I have found is the MSDS for Inswool basically telling me how bad this stuff is to breath. Fibers cause cancer. And other good stuff like that. his is a reprint of the post I presented in June. By code it is required. I don’t care what some installer or retailer tells you. Believing and putting your complete trust in them could make you dead wrong. Hearthnet would not exist if all went well. This is the one place where good advice code and safe installs are discussed.

Fitting a register plate or closure plate

An example of this is the high effeciench gas furnaces and hotwater heaters, use schedule 40 PVC drain pipe to direct vent there furnaces. The pvc pipe manufactures only test and certify their pipes for water flows and pressures. ITs up to the furnace manufactures to test the drain PVC pipe for their application.

The EPA requires re-certification every 5 years. In VC case, the non cat intrepid would not meet the EPA phase II regs, Reach up the through the hole in your closure plate (you did make a hole I hope - 1" larger diameter than your flue pipe) and grab the vitreous pipe and pull it down through the hole and down to and onto the stove. Do not forget to slide your 9″ sealing plate around the pipe when you do this – in readiness for screwing it up to your closure plate. It is the sealing plate that hides the gap between the flue pipe and the slightly over-large hole. Adaptors have various lengths of “nose”. A long-nose adaptor can be useful as it adds "telescopicity" to the system (I think I just made up a word). Cut the pipe hole round at first, and cut it at least 1/4” larger than the line – you’ll need the extra room. Cutting this hole can be accomplished in numerous ways: The attic scenario does not compare because you cannot have a sealed attic- there are always sources of airflow, and sources of humid air in an attic.This plate must be made of a solid, non-combustible material. These are often referred to as a closure or register plate but there is a difference between the two. Lets face the manufactures fudge the BTUs and areas that a stove will heat. They know more stoves will sell if the cost of installation is less. Telling an potential owner the cost just went up Before the closure plate design commences I usually connect my “adaptor” to the bottom of the chimney liner (adaptors can have differing lengths of nose and have two methods of attaching to the liner – bolts or self tappers). If using self tappers they will pass through the liner and both walls of the adaptor (choose a length so they only protrude a few mm into the inside surface of the adaptor). Better still buy our adaptor with captive wing nuts. NFPA 211 changed the Cross-sectional code for venting in to a larger flue. The former code allowed 3x the flue collar cross-sectional area . We will look at these two scenarios separately but if you are a number 2 ;-), then I would still read the instructions aimed at the number 1’s as a lot if this is relevant.

Use a long-nose adaptor as this means you have a few inches of telescopic safety. Why do you need this "telescopic" feature? Because your liner will not usually compress upwards. Because the bottom of your vitreous slides into your stove collar a whole inch or so. So you slide your vitreous over your adaptor snout and all the way up. Then you slide your stove underneath. Then you slide the vitreous down and into the stove. Position your stove on the hearth and plan your steel vitreous flue configuration. This may just be one piece of pipe or it may be more complicated. Same fireplace (middle). Hearth down first. And now you can see the first three 12mm cement-boards. I put the rear sheet in first (cut using angle grinder although a circular saw or jigsaw with a concrete cutting blade will do). On the rear sheet I ensure the factory cut edge is at the bottom..Cut on the larger line (including 1” flange), notch all four corners and fold down the 1” flange at about a 60 degree angle. For example a dramatic code change occured in 2003 NFPA 211. The manuals with that stove, could be printed in 2001 and they will not update the manual till re-certification occures Without an air source (open flue plate) condensation can't happen in a chimney because there is not a source for water vapor if it is sealed at top and bottom. Condensation just doesn't happen - condensation is carried by circulating air. A closure plate is used when a chimney liner, containing flue gases, is present. The closure plate is therefore only required to seal the chimney for cosmetic reasons, to stop soot old soot falling on the stove but also to stop heat disappearing up the chimney and being wasted. If a closure plate developed a fault (e.g.hole) smoke could NOT enter the room as the smoke is contained in a chimney liner. As this warm air rises, it needs to be replaced. So cold air is pulled in, usually from around doors and windows, creating the chilly draught that you can feel (and hear when it’s windy).