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Various types of cement are used in pizza oven. Using of cement depends on its working principle mostly. Following cements are used in making pizza oven widely.

Acid- resistant cement

Acid-resistant cement is one of most popular cements used in pizza oven. It has become popular for its resistant property against acid. It is composed of acid resistant aggregate, sodium silicate or soluble glass and additive. Acid resistant aggregate includes quartz and quartzite. Fluosilicate is used as additive, which increases resistance property of quartz or quartzite against acid. Silicate or soluble glass is used as binding material. Sodium silicate and potassium silicate is used as binding material in acid resistant cement.

This cement not only used as acid resistant cement but also acts as heat resistant coating. So it can be used as insulating material for your pizza oven. There is a problem of using this cement. Problem is that it may be attacked by high moisture during rainy season. Then it will be cracked and broken as granule from wall. But you can make it water resistant by adding 2% ceresit or 0.50% linseed. It will then act as water resistant material also. You can use this water and acid resistant cement outside of pizza oven.

Portland Pozzolana Cement (PPC)

Portland Pozzolana cement is produced by blending ordinary cement with pozzolanic material and gypsum. Sometimes, pozzolanic material and gypsum is ground separately and mixed with ordinary cement at a standard ratio. Pozzolanic material is well known as pozzolanic ash including calcined clay, volcanic ash, fly ash and silica fumes as well. Pozzolanic material is siliceous and aluminous substance and reacts with the calcium hydroxide of ordinary cement when water is available for reaction. By this reaction it produces calcium aluminate hydrate and calcium silicate hydrate, which are insoluble but good cementing material. This reaction is occurred at room temperature so you don’t need to be worried. You have to mix PPC with water and it will be high quality cementing material for the construction of pizza oven.

Benefits of using PPC:

1. It imparts compressive strength gradually.
2. It acts against sulphates.
3. During setting this cement produces less heat, which is very important for pizza oven construction.
4. Water-tightness is high for this cement.
5. High plasticity and workability of mortar is obtained if this cement is used.
6. It doesn’t get expansion during heating, and this property of PPC helps to give uniform shape of pizza oven.
7. It results in higher tensile strength.
8. It is less expensive than other modified cement.

Demerits of using PPC:

1. At early time, it imparts less compressive strength than any ordinary cement.
2. It is less resistant against weathering action and erosion.

Blast furnace cement

Blast furnace cement is produced from slag that is disposed as a waste material from pig-iron manufacturing industry. Slag contains all ingredients of cement like alumina, lime, good quality silica etc. Blast furnace cement shows characteristics like ordinary cement. But it is used in construction work including pizza oven construction. At earlier time of construction with this cement, it produces less strength but when it is cured properly it gives more strength than ordinary cement. This cement is so much economical than other cements available in market. It is not recommended to use inside of dome. You can use it only for outside of pizza oven. Considering its durability and economical issue, you can choose this cement for outside plastering of pizza oven.

Colored cement

Colored cement is just like ordinary cement, which is mixed with mineral pigments. This cement contains 5-10% coloring minerals. This cement may be found in different colors like red, green, brown, yellow etc. Here is a list of minerals used in ordinary cement to give different colors.

  • Green color comes from chromium oxide
  • Cobalt gives blue color
  • Brown, yellow and red color comes from ton oxide
  • Manganese oxide gives Black brown color

Colored cement is used for the decoration of external surface of construction work. Usually, it is used in making pizza oven to improve the outlook. This colored cement is available in hardware shop. Again, you can make this cement by mixing mineral pigments with ordinary cement. But one thing you have to consider in adding mineral pigments. More than 10% mineral pigments will reduce the strength of cement. So you have to add mineral pigments by keeping this issue in mind.

High alumina cement

High alumina cement is made of clinkers, which contains lime and bauxite. Bauxite is aluminium ore. Total alumina content of this cement will be more than 32% and ratio of alumina to lime will be 0.85:1.30. High alumina cement is used in all construction work including outside pizza oven. There are several advantages of using alumina cement in making pizza oven instead of any other ordinary cement.

Advantages of using high alumina cement:

1. Initial setting time is more than 2.5 hours and final setting time is nearly 5 hours. This cement gives time to mix and place mortar properly.
2. It is suitable to use for oven dome because it doesn’t change in property at high temperature.
3. During setting it emits heat, which makes it unaffected by frost.
4. High alumina cement is highly resistant to acid.
5. It sets rapidly and gives high strength to construction work. In first of construction it gives 40Pa compressive strength and after three days it becomes near about 50Pa.
6. Setting action of cement depends on chemical reaction and this cement doesn’t need to grind more into fine powder.

Disadvantages of using high alumina cement:

1. If this cement gets mixed with ordinary cement, it will not set properly and takes more time to be settled.
2. It isn’t perfect for mass construction because it produces high heat.
3. This cement is quietly expensive.

Hydrophobic cement

This cement contains hydrophobic admixtures, which makes this cement be less wetted. Acidol, oxidized petrolatum and naphthenesoap is widely used as hydrophobic admixtures. These admixtures form thin film around fine particles, which resists water to come in contact of cement particles. When hydrophobic cement is mixed with water, a film is developed on the surface of cement particles. This film prevents water to come in contact of fine particles and for that reason, this cement gives less strength to construction work at early days. But day by day, it produces more strength and after 25 working days it will same strength produced by Portland cement.

If you are staying at coastal area where raining is common experience, you should use this cement for making pizza oven. As it is hydrophobic, it resists rain to come into construction work and will make your oven long-lasting. This cement is quite costly, so you can use it outside of dome and hearth.

Rapid hardening cement

Nowadays, rapid hardening cement is widely used in making pizza oven. The initial and final setting period of this cement is same as Portland Pozzolana cement. High amount of tricalcium silicate (56%) makes to settle quickly and helps to impart strength at early age of construction.

Several advantages of using rapid hardening cement are as follows:

1. It can be used for any part of pizza oven like dome inside and outside wall as well.
2. This cement is perfect where early strength is prime concern.
3. It is perfect to use for oven floor because oven floor needs to carry high load of wood.
4. It protects construction work from freezing during winter season when snowing is common matter.
5. It is more durable than any ordinary cement and PPC as well.
6. This cement prevents shrinkage and highly resistant to acid action.
7. Compared to PPC this cement gives high compressive strength to pizza oven.
8. It is not costly like Portland Pozzolana cement.

Extra rapid hardening cement

This cements shorts setting time and accelerates hardening process. You may get confused that what is difference between rapid hardening cement and extra rapid hardening cement? Extra rapid hardening cement means extra strength to the construction work and it imparts nearly 25% strength more than rapid hardening cement. Strength of this cement isn’t more compared to Portland Pozzolana cement but not bad for using to pizza oven. Extra strength of this cement comes from extra calcium, which is ground and mixed with rapid hardening cement. But mixing limit of calcium chloride is maximum 2% to rapid hardening cement. Particle size of this cement will be less than 3 microns. As it is extra rapid hardening cement, so you have to use mortar within 20 minutes after mixing with sand and water. It is not so expansive like Portland Pozzolana cement, so you can choose it for making your outdoor pizza oven.

Quick setting cement

Quick setting cement contains small amount of aluminum sulphate. Aluminum sulphate is ground into powder and mixed with other ingredients of ordinary cement. Normally, gypsum is contained in ordinary cement, which retards the setting action greatly. To make quick setting cement, the proportion of this ingredient is lowered to increase the setting action. High amount of aluminum sulphate and low amount of gypsum makes the cement to be settled rapidly. It starts to be settled within five minutes after adding water in construction work. Within, 30 minutes it gets too hard like pebble or stone. As it settles quickly, you have to be conscious in making pizza oven with this cement because it may be hard before placing oven dome on oven floor. After all, this cement is great to use in worse weather for its quick setting property.

Sulphate resistant cement

Ordinary cement used in construction work may be attacked by sulphate, which will lead erosion of cementing work. Hydrate of calcium aluminium and calcium hydroxide of ordinary cement reacts with sulphate and form calcium aluminate and calcium sulphate respectively. These products cause expansion and disruption of hydrated and settled cement paste. If there is continuous raining this reaction rate is comparatively high. It will be same for your pizza oven if you use ordinary cement. Now, it is question what cement will be used to prevent this reaction?

To prevent this reaction you should use sulphate resistant cement. Sulphate resistant has been developed by lowing tricalcium aluminate content in ordinary cement and its limit is less than 5%. This will result in less reaction with sulphate and less erosion of construction work.

Where sulphate resistant cement will be used? You can use this cement anywhere mainly outside of construction work. It will be suitable for those places

  • where construction work are being damaged by alkaline
  • for basement of pizza oven where soil contains high amount of sulphate

Anyway, this cement is available at any hardware shop and less expansive. You can take decision for using this cement to make outside pizza oven. Moreover, it will make your pizza oven longer lasting.

Expanding cement

Expanding cement is improved by adding sulpho-aluminate and effective stabilizing agent to ordinary cement. This cement is used only used when other cements shrink remarkably. All cements are not perfect for construction of pizza oven because all parts of oven don’t get heated all time. Cement may get shrunk inside of dome because temperature is high. In this case, expanding cement can be used. But this cement isn't recommended to use for pizza oven all time.

Low heat cement

Cement is used in each construction work, which keeps all other ingredients together and imparts strength to construction work. At the time of setting, cement produces heat. If heat is excess during setting time, it will reduce the strength of construction work. This issue is considered in the construction of pizza oven. As a result, low heat cement is used in making pizza oven, which produces low heat at the setting time. This cement contains low amount of tricalcium aluminate and its limit up to 5%. But it contains high amount of dicalcium silicate and it may be 46%. Comparatively, it imparts low compressive strength. It’s initial setting time is about 30 minutes and final setting time is near about 10 hours.

White cement

White cement is ordinary cement prepared from such materials which is free from different coloring oxides like manganese, iron or chromium. It is prepared by following a different method. To prepare this cement oil is used as fuel instead of coal. It is creamy white in color and widely used for plaster work, floor finish, ornamental work of construction. It is also very cheap than any other cement. For that reason, it is used making pizza oven. It takes quite more time to set and its setting time is more than 30 minutes. It imparts high strength after being ordinary cement. Again its aesthetic value is high. If you want to add pebbles or marble on outside of pizza oven, it will be better to use white cement. It will give a different look to your pizza oven. You can prove it by using white cement on your pizza oven.

· 2 months ago

I have seen many videos that the builder says top mix perlite in my cement mix for building the inner portion of the dome. Is the true in needing to add this to my cement?