Frequently asked questions

Here are the most asked questions and the answers to these questions.

Planning and Operations

- What are the opening hours of the main office and warehouse?
- Our offices and warehouse are opened from 8.00 - 17.00 from Monday to Friday.

- What is the phone number of my internal contact at TPI-Polytechniek?
- We use one central phone number, after calling our main office we will redirect the call to your contact person. You can reach us at + 31 (0) 73 6569194


- Can TPI-Polytechniek organize the transport of my order?
- Yes, we can offer transport over land, air and sea, just ask us to add transport to your quotation.

- Is it possible to combine my order with other goods that need to be transported from another company in the Netherlands?
- Yes, ask our logistics department for details and we can look into the options of combining transport.

- Can I order goods directly from the warehouse in the United States?
- Yes, a selection of our program, focussed on the U.S. market, can be shipped directly from our warehouse in Mount Pleasant, Iowa.


- What are air inlets for poultry houses and pig farms?
- Air inlets in poultry houses and pig houses are responsible for providing good air distribution and the direction of fresh airflow throughout the building. Our inlet valves are properly designed and can be correctly managed. This positively influences animal performance and well-being. Exhaust fans create a negative pressure difference between the interior and exterior of modern, tightly-constructed farms. By creating this slight vacuum in the building, the outside atmospheric pressure literally pushes air into the house through any opening in the building. For the air inlets to be effective, it is important to keep the house as airtight as possible so that incoming fresh air flows through the ventilation inlets. If the house is not tight, fresh air will enter via any pathway (holes, cracks, open doors) leaving you with limited means to control the airflow pattern in the barn.

- Can I buy ventilation components directly from TPI-Polytechnics?
- We work through a dealer network and do not sell directly to end-users. This is because we produce components and not complete systems. System installers and equipment suppliers normally sell our products and include them in their service package. Get in touch with our sales team to learn about your local dealers.

- Are TPI-Polytechniek air inlets spring-closed or spring-opened?
- The majority of our inlets are produced to be spring-opened though spring closed is an option for almost all inlets. The spring can be easily converted from closing to opening or the other way around.

- Does TPI-Polytechniek offer complete ventilation systems?
- TPI-Polytechniek is supplier of components and in that sense we can supply all components necessary for your ventilation concept. However for a controller or winches/actuators, etc. you can report to one of the suppliers for these. Most of the time you can purchase your full ventilation system there, including TPI-inlets.

- Is insulation value really that important for air inlets?
- In extremely cold or hot areas the temperature differences outside and inside the house are so different that the complete climate system should be optimized in order to achieve the best possible production. An important feature of polyurethane next to insulation is preventing condensation and therefore wet spots in the house. Insulation naturally helps a lot in saving on energy costs.

- What is the difference in straight and curved inner flaps in air inlets?
- Straight flaps guide the air in a more upwards or straight direction when the inlets are opened. Curved flaps will also guide the air downwards to the animals and can, therefore, help to cool.

- Why are there bottom hinged and middle hinged inlets?
- Bottom hinged inlets do not guide any air down towards the animals in earlier stages of ventilation. Middle hinged air inlets can do just that and therefore help to cool the animals.