Kiln posts look like the least exciting part of a kiln, but they decide how much fits in each firing and whether a shelf sits flat. The right set of kiln posts is a range of heights in one width, from a supplier that states a cone rating, bought in threes or fours so every shelf has matched supports.
This guide is research-based. We compared supplier listings from The Ceramic Shop, Clay-King, Smith-Sharpe (kilnshelf.com) and School Specialty, Skutt's 2025 price list, kiln furniture kit contents from L&L and Skutt, kiln manuals from L&L and Olympic, and Ceramics Monthly's technical notes on kiln furniture. We did not fire these posts ourselves. This page covers posts only; shelves, full furniture kits and kiln wash are in our kiln shelves and furniture guide.
Kiln post picks at a glance
- Best overall: The Ceramic Shop 1.5 in square posts (rated to cone 10 by the maker, 1/2 to 12 in, sold singly or by the dozen)
- Best for test and glass kilns: The Ceramic Shop 1 in posts (slim 1 x 1 in section that saves shelf space)
- Best kiln maker set: Skutt Small Post Assortment (three each of 1 to 6 in, for 818 size kilns and smaller)
- Widest height range: Smith-Sharpe square cordierite posts (two widths, 1/2 to 12 in)
- Best for heavy shelves: Clay-King 1.5 in wide posts (sizes up to 12 in, including 7 in)
- Best Amazon pack: Nuanchu 8-pack, 4 x 1 in high-alumina posts (listing specs only)
Kiln posts compared
| Product | Section | Heights | Material | Rating stated | Buy |
|---|---|---|---|---|---|
| The Ceramic Shop 1.5 in posts | 1.5 x 1.5 in | 1/2 to 12 in | Ceramic (type not named) | Cone 10 | Check price |
| The Ceramic Shop 1 in posts | 1 x 1 in | 1/2 to 6 in | Ceramic (type not named) | Not listed on the 1 in page | Check price |
| Skutt Small Post Assortment | 1.5 in (Skutt posts) | 3 each of 1 to 6 in | Firebrick per one dealer | Not published | Check price |
| Smith-Sharpe cordierite posts | 1 in or 1 5/8 in | 1/2 to 12 in | Cordierite | Not listed | Check price |
| Clay-King 1.5 in posts | About 1.5 in | 1/2 to 12 in | Not stated | Not stated | Check price |
| Nuanchu 8-pack | 1 in | 4 in only | High alumina (listing) | Not published | Check price |
"Section" is the width of the post's square face. Height is what sets the gap between shelves.
The Ceramic Shop 1.5 in square kiln posts
These are the closest thing to a standard kiln post for a home pottery kiln. The Ceramic Shop makes them in its own shop, gives a 1.5 x 1.5 inch cross-section and says they "can be fired up to cone 10". That rating covers bisque at cone 04, mid-fire glaze at cone 5 to 6 and high-fire stoneware, which is more than most home potters need.
The range is wide. Single posts run from 1/2 inch to 12 inches tall, and the common heights also come by the dozen, which is the cheapest way to get matched sets. A dozen 1 inch posts was listed at about $15 to $16 in October 2026; taller posts cost more. The shop also sells triangular posts in 2.5 and 5 inch heights in packs of 12, for anyone who prefers three-sided supports.
One detail matters for loading: the listing says lengths may vary by plus or minus 1/16 inch. That is normal for kiln furniture, but it means two "4 inch" posts can differ slightly. Stand the posts for one shelf side by side before loading, and use the closest matched three or four under each shelf.
- Cross-section: 1.5 x 1.5 in
- Heights: 1/2 to 12 in singly; common heights by the dozen
- Rating: up to cone 10 (maker listing)
- Tolerance: plus or minus 1/16 in on length
- Material: "durable ceramic composition"; the exact refractory is not named
Pros
- Cone 10 rating stated by the maker
- Full height range in one width
- Dozen packs keep heights matched
Cons
- Refractory type not published
- Heavier and wider than you need in a tiny test kiln
Who should skip it: Owners of a test kiln with shelves under 9 inches across, where 1 inch posts leave more room for tiles.
The Ceramic Shop 1 in posts for small kilns
In a small kiln every square inch of shelf counts. These slimmer posts have a 1 x 1 inch cross-section, and The Ceramic Shop says they are "designed to maximize space in smaller kilns like glass and test kilns". On a 7 inch or 9 inch shelf, a narrower post can be the difference between three test tiles in a row and four.
The shop sells them by the dozen in 1/2 to 6 inch heights, and the shop notes that it started offering 1 inch thick posts because customers asked for them for glass kilns and smaller pottery kilns. That makes them a natural partner for a test kiln such as a Paragon Caldera or L&L Plug-n-Fire, where the shelves are small and the loads are light.
Be aware of the rating gap. The shop's category page says its posts can be fired to cone 10, but the single listing we checked for a 1 x 1 inch post does not state a cone figure. If you fire to cone 10, ask the shop to confirm before you load heavy porcelain on them. Thin posts also carry less weight than wide ones, so keep them for small shelves and light work.
- Cross-section: 1 x 1 in
- Heights: 1/2 to 6 in by the dozen
- Intended use: glass kilns, test kilns and small pottery kilns (maker)
- Rating: cone 10 on the category page; not repeated on the 1 in listing
Pros
- Saves shelf space in small kilns
- Sold in matched dozens
- Made by the seller
Cons
- Cone rating not on the individual listing
- Not meant for big, heavy shelves
Who should skip it: Anyone loading full-size 18 inch or 23 inch shelves with stoneware, who should use 1.5 inch posts.
Skutt Small Post Assortment
If you own a Skutt and want posts from the same maker as your kiln, this is the simplest order. Skutt's 2025 price list describes the small post assortment as three each of 1 inch through 6 inch lengths, for kilns 818 and smaller, so you get 18 posts in six heights. The list price sat just under $100; check the live price at your dealer.
Three of each height is a sensible design: three posts is the support count Skutt and L&L both describe for a shelf, so each height in the box can hold one shelf level. For bigger kilns, Skutt lists a large assortment with six each of 1 to 6 inches for the 1018 and larger, and individual 1.5 inch posts from 1/2 inch to 12 inches if you need to fill gaps.
The weak spot is documentation. Skutt's price list gives the contents but not the material or a cone rating, and School Specialty's listing calls the material "firebrick", which we could not confirm with Skutt. Skutt kilns fire to cone 10 and Skutt sells these as matched furniture, but if the rating matters to you, ask your dealer for the spec.
- Contents: 3 each of 1, 2, 3, 4, 5 and 6 in posts (Skutt 2025 price list)
- Fits: Skutt 818 and smaller kilns (other brands fine if heights suit)
- Individual Skutt posts: 1.5 in wide, 1/2 to 12 in tall
- Material and rating: not published by the maker; "firebrick" per School Specialty
Pros
- Six heights in one box
- Three per height matches standard shelf support
- Kiln maker part
Cons
- No published rating or material
- No 1/2 in posts in the small box
- Dealer order
Who should skip it: Owners of a 23 inch kiln such as the KM-1027, who should look at the large assortment or a furniture kit.
Smith-Sharpe square cordierite posts (kilnshelf.com)
Smith-Sharpe, the company behind kilnshelf.com and the main US outlet for Advancer shelves, sells plain square cordierite posts in two widths. The 1 inch posts run from 1/2 inch to 10 inches, and the wider 1 5/8 inch posts from 1/2 inch to 12 inches. Single posts were listed at roughly $1 to $8 each in October 2026, depending on size; check the live price.
Cordierite is the usual material for electric kiln posts because it handles repeated heating and cooling well and is inexpensive. Ceramics Monthly lists mullite, cordierite and silicon carbide as the common refractories for shelves and posts, with cordierite the least costly. The listing does not give a cone rating, so treat these as standard electric kiln furniture and ask before using them under cone 10 loads.
The 1 5/8 inch width is a little wider than the 1.5 inch posts most US kiln makers ship. That does no harm, since height is what counts, but do not mix brands under one shelf without checking heights side by side, because small differences between makers can make a shelf rock.
- Material: cordierite (listing)
- Widths: 1 in and 1 5/8 in square
- Heights: 1/2 to 10 in (1 in posts); 1/2 to 12 in (1 5/8 in posts)
- Rating: not listed
Pros
- Many heights in two widths
- Low cost per post
- Named material
Cons
- No cone rating on the listing
- 1 5/8 in width differs from most kiln maker posts
Who should skip it: Buyers who want one boxed assortment instead of picking posts one by one.
Clay-King 1.5 in wide kiln posts
Clay-King sells two post widths and is clear about when to use each. Its 1.5 inch posts come in 1/2, 1, 2, 3, 4, 5, 6, 7, 8, 10 and 12 inch heights, and the listing says "If you have large shelves or need to hold a lot of weight these are the posts for you." Prices ran from about $2 to $12 per post depending on height in October 2026.
The 7 inch size is useful and less common than you might think. A 7 inch post gives room for a typical mug with a little air above it on a mid shelf, without jumping to 8 inches and wasting height. The 10 and 12 inch posts suit a top layer of vases in a deep kiln.
For small kilns, Clay-King's 1 inch posts cover 1/2 to 8 inches at about $1.60 to $6.50 each and are suggested for "smaller shelves where conserving space is key". Clay-King also lists a small kit of 15 posts, three each of five heights, but it was out of stock when we checked. Neither listing states a material or cone rating.
- Width: about 1.5 in ("roughly 1.5 in wide")
- Heights: 1/2, 1, 2, 3, 4, 5, 6, 7, 8, 10 and 12 in
- Material and rating: not stated
- Sister product: 1 in wide posts, 1/2 to 8 in
Pros
- Many heights including 7 in
- Clear advice on width
- Stocked by a large US supplier
Cons
- No material or cone rating published
- Sold one at a time
Who should skip it: Anyone who needs a published cone 10 rating before buying.
Nuanchu 8-Pack Kiln Posts
If you want posts in a hurry and Amazon is your store, this pack gives eight posts, 4 inches tall and 1 inch across, described in the listing as high alumina. Four inches is the height most home potters reach for first, because it clears a short bowl or a stack of tiles on a lower shelf.
Eight posts at one height is enough to set two shelves on four posts or two shelves on three posts with spares. That makes this a good top-up for a furniture kit that came with only a few posts of each height. High-alumina posts are generally dense and strong, but this listing gives no cone rating and we found no maker spec sheet.
Treat the first few firings as a trial. Load them under a light shelf first, look for cracks, bowing or a lean afterward, and only then trust them under heavy stoneware. As with any post, scrape glaze drips off the ends so shelves sit level.
- Contents: 8 posts (listing)
- Size: 4 in tall x 1 in (listing)
- Material: high alumina (listing)
- Rating: not published by the maker
Pros
- Quick to get
- Common 4 in height
- Works in any kiln
Cons
- One height only
- Listing-only specs with no cone rating
Who should skip it: Anyone who needs several heights or a stated cone 10 rating.
Starter post sets by kiln size
Kiln makers' own furniture kits are a good guide to how many posts, and which heights, a kiln of a given size needs. These are the post counts the makers list:
| Kiln | Kit posts (maker) | Post width |
|---|---|---|
| L&L Plug-n-Fire (8 x 8 x 9 in test kiln) | Three 3 in posts | Not stated |
| Skutt GlazeTech (15 in, 9 in deep) | Twelve 1 in posts | Not stated |
| L&L DLH11 test kilns (11 in round) | Four each of 1/2, 1, 2 and 4 in | 1.5 in square |
| Skutt 818 size and smaller | Three each of 1 to 6 in | 1.5 in |
| Skutt KM-1027 kit | Six each of 1 to 6 in (36 posts) | Not stated |
| L&L eFL1626 front-loader (6.6 cu ft) | Six each of 1/2, 1, 2, 4, 6 and 8 in | Square, size not stated |
The pattern is clear: small kilns need short posts and few of them, while 18 inch kilns need three or four of every height from 1 to 6 inches, and big kilns add taller sizes. How many posts each shelf should sit on is covered in our shelves and furniture guide.
How to choose kiln posts
Pick heights from your work, not from the kiln
Measure your tallest common pieces and add about 1/2 inch of air above them. Mugs, tumblers and bowls set most of your shelf gaps, so buy those heights in quantity and add a few tall posts for vases. Posts between 1 and 6 inches do most of the work in an 18 inch kiln, which is why Skutt's assortments stop at 6 inches. Short 1/2 inch posts raise the bottom shelf off the floor; Olympic's manual says to load the bottom layer on a shelf "supported 1/2 inch from the bottom" rather than directly on the kiln floor.
Width: 1 in, 1.5 in or 1 5/8 in
Width trades shelf space for strength and stability. Clay-King recommends its 1.5 inch posts for large shelves or heavy loads and 1 inch posts for smaller shelves where space matters. In practice, 1.5 inch posts are the default for 15 inch and larger kilns, and 1 inch posts suit test, glass and craft kilns. Tall, thin posts are the least stable combination, so choose the wider size for your tallest posts.
Materials: cordierite, mullite and silicon carbide
Ceramics Monthly's kiln furniture primer names mullite, cordierite and silicon carbide as the usual refractories for shelves and posts. Cordierite is the least expensive and copes well with repeated heating and cooling, which is why most electric kiln posts use it. High-alumina and mullite posts are stronger at high temperature. Silicon carbide is the strongest but costs more and, the article notes, resists thermal shock less well than cordierite. For a home electric kiln firing to cone 6 or cone 10, cordierite or high-alumina posts from a supplier that states a cone rating are enough.
Square, triangular and round posts
Square posts are the standard, and every product in this guide uses them except The Ceramic Shop's triangular option. Triangular posts tuck into the corners of shelves and leave a little more room for ware. Round and hollow tube posts also exist; they are lighter, but they are less common in hobby catalogs. Whatever the shape, use one style under a shelf so the heights match.
Stacking posts and turning them on their side
You can stack two shorter posts to make a taller support, and The Ceramic Shop describes its posts as stackable to set shelf height. A single post of the right height is more stable than a stack, so keep stacks short and straight. Posts can also be laid on their side when the side dimension gives the height you need; The Ceramic Shop told a forum member they can be used that way but are "most stable" standing on their ends.
Leveling with wadding
When a shelf rocks, the cause is usually one post a little short or a drip of glaze on a post end. Swap posts first: with a 1/16 inch tolerance on many posts, a different post of the same height often fixes it. Some potters press a small pad of wadding (a refractory putty) between post and shelf to level and stop sticking. If you use it, follow the supplier's directions and keep it thin, and never pack wadding into a gap to make up for a badly matched post.
Placement rules from the kiln makers
Kiln manuals add a few rules that apply to posts as much as to shelves. L&L's manual says not to let shelves, posts or ware touch the thermocouples, because that can affect the temperature reading. Olympic's manual asks you to keep shelves and ware at least 1 inch from the thermocouple and 1/2 inch from the kiln wall, and to leave at least one element groove between the top shelf and the top of the kiln. Stack posts directly above the posts on the shelf below so the load runs straight down to the floor. Our guide to loading a kiln walks through a full load.
Can you make your own kiln posts?
Some potters make posts from high-fire clay, but a homemade post has no tested rating, can hide cracks and shrinks as it fires, so it may not match commercial posts. Bought posts cost a few dollars each, which is little next to the risk of a shelf full of pots falling. If you do make supports, keep them for light, low items and fire them first on their own.
Care, cracks and when to replace a post
Check posts each time you unload. Retire any post that is cracked, chipped on an end, bowed or leaning, because posts tend to fail without warning under a hot, heavy shelf. Scrape or grind glaze drips off post ends so shelves sit flat. Store posts dry; Ceramics Monthly warns that refractories can absorb moisture and may burst when it turns to steam in a firing.
Grinding glaze drips off posts and shelves makes fine dust that contains crystalline silica. Grind outdoors or with dust control, wear a NIOSH-approved respirator and eye protection, and clean up with a damp sponge or mop, never by dry sweeping. Kiln furniture is hot long after the kiln display reads safe, so unload with kiln gloves and let the kiln cool fully.
What else to buy with posts
Posts go with shelves sized to your kiln and with kiln wash on shelf tops; see our kiln wash page for how to apply it. For glazed bases on low-fire work, kiln stilts do a different job from posts: they lift a piece, not a shelf. If you are still choosing a kiln, our pottery kiln guide lists the shelf sizes each one takes.
Sources: The Ceramic Shop kiln post category and listings (1 in dozen, 2 x 1 in post); Clay-King kiln post category, 1 in and 1.5 in post listings and small kiln post kit; kilnshelf.com (Smith-Sharpe) kiln post category, both pages; Skutt Ceramic Kiln and Accessories Price List 2025 (post assortments, individual posts, GlazeTech furniture kit); School Specialty listing for the Skutt Small Post Assortment; L&L Kilns pages for the Plug-n-Fire, DLH11-D, DLH11-DX and eFL1626 (furniture kit contents) and the L&L Easy-Fire instruction manual; Olympic Kilns electric kiln manual; Ceramics Monthly, "Techno File: Kiln Furniture 101"; Ceramic Arts Daily community thread on setting posts on their sides; Amazon listing for the Nuanchu 8-pack (listing specs only). Specs checked October 2026.