Conditions for the validity of Salaah

Intention of different nafl salaah when performing one nafl salaah

Q: I came to know by one of the dawat-o-tabligh elders that we can make intention of many different namazes (e.g: if we are praying ishraq then we can make intention of tahiyaatul wudhu, tahiyyatul masjid, salaatul hajat, salaatul taubah, etc.)

1. Is it true?

2. How many total extra niyyats can we make for a two rakat nafil?

3. Can we do the same for zohar, maghrib and isha nafl prayers?

Checking for qibla with an app

Q: On a trip out of town that necessitated qasar salaah, my sister checked the qibla direction using 2/3 apps. 2 gave a certain direction and the 3rd gave a different direction. We thus read our salaah according to the qibla direction from the two that were the same. However on the day we were leaving, I was on the balcony watching the sunrise and realised the sun was rising on the exact opposite direction of our qibla direction. In my understanding the qibla direction is north east and the sun rises in the east which meant our qibla was incorrect. Is this right? This doubt is lingering on my mind. Do I have to repeat my salaah? 

Fowl droppings

Q: A fowl came into the home and soiled the carpet with droppings. Should I wash the soiled area only, or do I have to wash the entire carpet? If salaah was performed on the clean portion of the carpet before the entire carpet was washed, will the salaah be valid?

Making the intention of Zuhr salaah when performing Asr salaah

Q:

1. I was praying behind the imaam. The imaam was praying asar salaah and I made intention of zohar salaah and I know that it was asar after the prayer. Is my prayer valid or do I have to redo my asar salah?

2. If I am praying alone or with the imam and it is asar time and I make intention of zohar forgetfully and after one rakaah I realize that it is asar, do I have to redo my prayer?

3. What if it was just at the begninng i.e I am doing recitation before fatiha and I realize that it is asar, do I have to redo my niyyah and start over?

Wearing an ihraam where parts of the skin is visible

Q: Zaid has a towel ihraam which is made in such a way that there are very small holes in the ihraam cloth. When wearing the ihraam, little skin is visible from the holes. Zaid prayed salaah, did his umrah and Hajj with the above mentioned ihraam on. According to Shariah is his salaah, umrah and Hajj valid? If it isn't valid, what should be done to compensate?