The location of the only burial shaft (No. 1) is inside the body of the mastaba, close to its northern wall. It has no logical connection with the two false doors sculpted and inscribed for Merefnebef in the main chapel's west wall. The date of this shaft may be earlier than that of the vizier's mastaba, by which fact it would thus appear to have been reused, i.e. adopted or even usurped. A possible connection may have existed between this shaft and the false door set in the secondary (east) chapel of the tomb, for they are located close to each other. This may explain why this new chapel was placed in the north of the mastaba's east wall (near the shaft), but it does not explain why the shaft is located so unusually, towards the middle of the northern part of the mastaba.

The chamber had been cut in the bedrock, and its upper part, above the level of the bedrock, is preserved up to the height of about 2.50m and built of oblong, irregular local stones (). The shaft is 14.40m deep with an opening of approx 2.30 x 2.30m. At the bottom, the shaft opens directly into the burial chamber situated on its western side. The burial chamber, which is very irregular in shape, has a quasi-rectangular plan, oriented N-S (). It measures about 5.42m N-S, 3.15m E-W and is 2.70m high. The walls of the chamber are uneven and only roughly worked.

In the middle of the chamber is a sarcophagus roughly carved out of hard, white limestone, approx. 2.95m long, 1.35m wide and 1.23m high. Its lid is 0.58m thick and made of the same stone. The sarcophagus and the lid bear traces of whitewash, but otherwise they remained undecorated. Behind the sarcophagus, along the western wall of the burial chamber, there is a niche cut into the rock, intended for the lid before the burial.

When found and excavated in modern times, the shaft was filled with sand which had blown into it. The burial chamber was partially filled with fragments of local rock of various sizes as well as fragmentary and powdered mud bricks, filling the chamber above the height of the sarcophagus. The upper layer of the fill also contained large blocks which had fallen down from the rock-cut roof of the chamber.
In front of the rubble were found six vessels : 2 beer jars, two dishes, a bowl and a vase in the shape of sTt-bread. The 2 jars contained a blackish grey powder, as found also in other tombs of the Old Kingdom. This powder replaced, in quantity and weight, the beer which should have been there (). So, the container remained full for the eternity.
Hundreds of fragments of a special jars were recovered in the shaft : jars with ashes, which were part of the funerary offering. These jars were probably filled of the remains of the last funerary meal taken in front of the tomb.
The burial chamber had obviously been pillaged, and it is possible that this vandalism took place shortly after the funeral ceremony. The sarcophagus was found empty, with a stone inserted under the south-eastern corner of its lid. The body had been dragged out and left on top of the lid. Although the body was reduced to a skeleton, upon discovery the bones remained in an anatomical position (with exception of the skull) which could suggest that the robbery occurred when the soft tissues had not yet decayed ().

The tomb of vizier Merefnebef being composed of a mastaba made of mud bricks, a chapel in excavated into the bedrock (under the mastaba), and of a second chapel added to the east wall of the mastaba, has obviously been constructed in several stages.
Merefnebef may have begun his career under the reign of Teti, and finished it under the short reign of Userkare, and he seems to have died under the reign of Pepy I.

a) - the digging of an oblong chapel; b) - lower courtyard (1a) ; c) - upper oblong courtyard; d) - mastaba in mud bricks above the chapel.
It is likely that only the inside of the chapel was decorated at the end of this phase.
At this time, Merefnebef is classified among the courtiers of intermediate rank, thus explaining the size and the modest shape of the monument.

This seems to start at the time of the nomination of Merefnebef as vizier, probably under Userkare. Then, the facade was engraved, with numerous repetitions of the word "vizier". At this point, an enlargement and monumentalisation of this modest burial was considered, but never achieved. The stopping of the work could coincide, either with the death of Merefnebef, or with his political disgrace after the death of Userkare.

A very short time after the death of Merefnebef, and certainly under the reign of Pepy I, conflicts broke out between the sons of the vizier. This seems to have resulted in the youngest son, who carried his father's names of Merefnebef and Fefi, had the names and images of his brothers erased (the exceptions being on the east wall of the chapel.
But added to the domestic conflict is a political conflict. The word "king" was chiselled out in the inscriptions mentioning the deceased as "Honoured by the king". In a specific title of the father; "king" is even replaced in one occurrence by the word "desert". Considering that this action probably took place during the time of Pepy I, it is tempting to identify the anonymous "king" as Userkare.
There is no doubt that it was done at the beginning of the reign of Pepy I, because this sovereign vandalised in the same way other tombs of nobles at Saqqarah.

However, the son Merefnebef / Fefi didn't just destroy, he also restored : starting at the entry passageway, he tried to eliminate his brothers; but he didn't fail to add some scenes of his own, showing himself with his wife Hemi (east wall, south side). This could therefore be classed as partial usurpation of the father's monument by the son.

A short time after these events, possibly again under Pepy I, or under his successor Merenre, the mud brick mastaba collapsed into the lower courtyard (N°1), blocking the entry of the chapel for millennia. The family members, didn't try to clear it, but may even have been responsible for the reinforced cover wall, probably to protect the tomb.

Some time after, in any case before the end of the 6th Dynasty, some family's members, anxious to resume a cult to this ancestor, dead for a long time but still remembered, built a small cult chapel. This was constructed against the east wall of his mud brick mastaba, near its northern end.
This smaller and simpler construction, more symbolic than anything else, yet it included a monumental false door of hard limestone, surmounted by a large lintel. The door was discovered upside down in the sand (). It has six representations of the vizier, symmetrically distributed in relation to the central axis. Surprisingly, the word nswt (king) has been erased in the title "Honoured by the king", as it had been in the chapel. It signifies that, for years after the death of Merefnebef, his family was always divided between the "pro" and the "anti" !

According to the results of the ceremonological analyses, it seems that the funeral cult for Merefnebef continued in the west chapel until the reign of Merenre, and in the east chapel until the end of the VIth Dynasty.

A full size replica of the chapel has been created and is on exhibition in Warsaw.